References and bibliography

General

In standard documents typically there are two types of references, namely the “Normative references” and the “Bibliography” (informative references).

The following fixed clause names identifies a bibliography:

Normative references
Bibliography

Every bibliographic section must be preceded by the style attribute [bibliography] so that references they contain may be recognized as such:

[bibliography]
== Bibliography

* [[[id1,1]]] _First reference_
* [[[id2,2]]] _Second reference_
* [[[id3,3]]] _Third reference_

Example 1. Example of creating the “Normative references” clause in an ISO deliverable

In ISO, the “Normative references” clause is stated in Clause 2 (ISO Directives Part 2, Clause 15), while the “Bibliography” section is set as the last unnumbered section at the end of document (ISO Directives Part 2, Clause 21). It should be typeset as the following:

...
// This is Clause 2 of an ISO deliverable
[bibliography]
== Normative references

* [[[ISO8601-1,ISO 8601-1:2019]]] _First normative reference_
* [[[ISO8601-2,ISO 8601-2:2019]]] _Second normative reference_

...

// This is after the last clause of an ISO deliverable
[bibliography]
== Bibliography

* [[[ISO10241-1,ISO 10241-1]]] _First bibliographic reference_
...

Normative and informative references are normally recognised by the distinct title given them, specific to the flavour; however, the normative status of the bibliographic section can be given explicitly with a normative boolean attribute [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.8.7]:

[bibliography,normative=true]
== References normative

...

[bibliography,normative=false]
== References informative

Bibliography sections can be split into subsections. Metanorma AsciiDoc requires each subsection containing references to be styled with [bibliography], and raises an (ignorable) warning if the subsections are contained in a section itself styled with [bibliography].

Example 2. Example of having multiple bibliography sub-sections

== Bibliography

[bibliography]
=== Part 1

* [[[id1,1]]] _First reference_
* [[[id2,2]]] _Second reference_
* [[[id3,3]]] _Third reference_

[bibliography]
=== Part 2

* [[[id4,4]]] _Fourth reference_
* [[[id5,5]]] _Fifth reference_
* [[[id6,6]]] _Sixth reference_

Note	A warning will be raised if `== Bibliography` in the above EXAMPLE was preceded by `[bibliography]`.

Note

In Metanorma IETF, the bibliography sections “Normative references” and “Informative references” are separate, where the “Informative references” section is optional:

[bibliography]
== Normative references

* [[[id1,1]]], _First normative reference_
...

// Optional
[bibliography]
== Informative references

* [[[idn, n]]], _First informative reference_
...

See References (AsciiRFC v3) for further details.

Numbering and ordering

All entries in a bibliography section, whether standards or generic, are renumbered incrementally in the Metanorma XML. If the number for generic references is updated, all citations of that reference will be updated as well.

By default, Metanorma does not change the ordering of references in the bibliography sections from what has been entered by the authors. Some Metanorma flavours will reorder references to suit document requirements.

That said, all references in a references section are grouped together, even if there is intervening text in the source document. Only notes are left attached to their reference, in order to enable annotated bibliographies.

Predefined text

Any initial text in a Normative Reference section (before the first reference) is replaced by predefined text specific to the Metanorma flavour.

In order to override this, initial text can be provided by the user as a open block with “boilerplate” [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.3.0] (formerly: a note of type “boilerplate” [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.9.2])

== Normative references

[.boilerplate]
--
The following contract document is referred to in the text in such a
way that some or all of its content constitutes requirements of this
document.
--

Entering individual references

General

Bibliographic entries are entered as unordered lists in Metanorma AsciiDoc within a dedicated clause or section.

A single bibliographic entry must be preceded by a bibliographic anchor, in triple brackets, as shown in the following syntax:

* [[[{anchor},{document identifier or reference tag}]]], _{reference list text}_

The following data elements are needed in a reference entry:

anchor
document identifier or reference tag
reference list text

anchor

a user-defined string that is an internal identifier used for cross-referencing within the current document. This string is typically composed with ASCII characters and hyphens or underscores. Other characters are not recommended.

Warning
See Anchor ID syntax for allowed characters in anchor IDs.

document identifier

the authoritative document identifier of the bibliographic item. Standardized deliverables such as International Standards from ISO and IEC are assigned authoritative identifiers, such as "ISO 8601-1" or "ISO 8601-1:2019". This is often used for auto-fetching of bibliographic details (see auto-fetch). When a document identifier is used, the reference tag is also set to be identical.

reference tag

a user-defined string used for rendering a mention of this bibliographic item in the resulting output. This is typically in a format defined by the user, or publication conventions adopted by the user. See Reference tags for more information.

reference list text

a user-defined, pre-formatted description about the bibliographic item. This text is either formatted according to ISO 690:2021, or publication conventions like MLA, APA or the Chicago Manual of Style. If encoded in the ISO 690:2021 format, the resulting citation will be a machine-readable one.

Types of references

There are multiple ways of entering bibliographic items in Metanorma for referencing as shown in Entering bibliographic references.

The most commonly-used methods are:

Automatic fetching via Relaton ("auto-fetch");
Annotating pre-formatted references using semantic elements;
Entering with AsciiBib; and
Entering pre-formatted references.

It is strongly recommended that the automatic fetching method be used for data consistency and ease of use whenever possible (especially for references to standards supported by Relaton).

If automatic fetching is not available for a particular reference, and if machine-readability or accurate rendering is important, either use annotated citation spans or AsciiBib for entering structured and detailed bibliographic information within a document.

The basic form of a reference is a pre-formatted reference, which relies on the user to supply a properly formatted reference.

Reference tags

Implied reference tags

Bibliographic entries for standards are expected to have the standard document identifier as the item label. References to well-defined standards codes use the document identifiers for citations (e.g. ISO 20483:2013).

This is entered as:

* [[[{anchor},{document identifier as reference tag}]]], _{reference list text}_

Example 3. Example of implied reference tags

* [[[ISO20483,ISO 20483:2013]]], _Cereals and cereal products -- Determination of moisture content -- Reference method_
* [[[ISO6540,ISO 6540:1980]]]. _Maize -- Determination of moisture content (on milled grains and on whole grains)_

gets rendered as:

ISO 20483:2013. Cereals and cereal products — Determination of moisture content — Reference method

ISO 6540:1980. Maize — Determination of moisture content (on milled grains and on whole grains)

A well-defined standards code as the item label will by default result in the reference details for the bibliographic entry being auto-fetched, provided that auto-fetching has been defined for that class of standard (Automatic fetching via Relaton ("auto-fetch")).

Overriding fetching

If an individual reference identifier is wrapped in nofetch(), the reference details for that item are not looked up, though other items still will be:

[bibliography]
== Bibliography

* [[[ref1,nofetch(ISO 639-1)]]], ISO 639-1.
* [[[ref2,ISO 639-2]]], ISO 639-2.

Numeric reference tags

Generic references in bibliographies, as opposed to standards references, use numbers, which are rendered bracketed, like [1].

This is entered as:

* [[[{anchor},{number}]]], _{reference list text}_

Example 4. Example of specifying numeric reference tags

* [[[ISO20483,1]]], _ISO 20483:2013 Cereals and cereal products -- Determination of moisture content -- Reference method_
* [[[ISO6540,1]]]. _ISO 6540:1980 Maize -- Determination of moisture content (on milled grains and on whole grains)_

gets rendered as:

[1] ISO 20483:2013 Cereals and cereal products — Determination of moisture content — Reference method

[2] ISO 6540:1980 Maize — Determination of moisture content (on milled grains and on whole grains)

Note	To indicate usage of the numeric reference system, any number can be entered into the reference tag field. All references are automatically re-sorted and auto-incremented during compilation.

Normative references must use either standard document identifiers, or named reference tags.

Note

Numeric references cannot be used for entries in normative references, as bibliography numbering starts at 1. Execution will abort if a numeric reference tag is found in normative references, in order to prevent numbering confusion [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.8.4].

Named reference tags

General

References can be tagged with user-supplied alphanumeric labels, in addition to numbers or standard document identifiers.

These are indicated by wrapping the label within the bibliographic anchor in brackets.

Named reference tag with fully specified bibliographic entry

If the reference text is fully specified, and where no auto-fetching of the bibliographic entry is necessary, a user-supplied label is entered using the following syntax:

* [[[{anchor},({reference tag})]]], _{reference list text}_

Note	These alphanumeric labels will not result in the bibliographic entry being auto-fetched.

Example 5. Sample named reference tag with fully specified bibliographic entry

* [[[ISO20483,(CerMoist)]]], _ISO 20483:2013 Cereals and cereal products -- Determination of moisture content -- Reference method_
* [[[ISO6540,(MaiMoist)]]]. _ISO 6540:1980 Maize -- Determination of moisture content (on milled grains and on whole grains)_

gets rendered as:

[CerMoist] ISO 20483:2013 Cereals and cereal products — Determination of moisture content — Reference method

[MaiMoist] ISO 6540:1980 Maize — Determination of moisture content (on milled grains and on whole grains)

Named reference tag with automatic reference fetching

Users can provide both their own alphanumeric label, and the well-defined reference identification code for the standards document.

This will result in the bibliographic entry being auto-fetched, so long as that auto-fetch is supported for that class of references [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.3.15]:

If a named reference is to be auto-fetched, it is entered by prefixing the named reference tag (in parentheses) to the document identifier:

* [[[{anchor},({reference tag}){reference identification code}]]], _{reference list text}_

Example 6. Example of named reference tag fetched automatically

* [[[ISO20483,(CerMoist)ISO 20483]]], _ISO 20483:2013 Cereals and cereal products -- Determination of moisture content -- Reference method_
* [[[ISO6540,(MaiMoist)ISO 6540]]]. _ISO 6540:1980 Maize -- Determination of moisture content (on milled grains and on whole grains)_

Rich-text formatting is supported within the named reference tag, including footnotes [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.0.3].

This is useful for cases where a cited reference is out-of-date but unsuitable to be updated.

Example 7. Example of rich-text formatting in named reference tag

* [[[ISO9000,(ISO 9000:2005 footnote:[Superseded by ISO 9000:2015.])ISO 9000:2005]]]

Example 8. Example of added footnote to a named reference tag (ISO/IEC 17025:2017)

* [[[ISO_IEC_Guide_99_2007,(ISO/IEC Guide 99:2007 footnote:[Also known as JCGM 200])ISO/IEC Guide 99:2007]]]

* [[[ISO_IEC_17000_2004,ISO/IEC 17000:2004]]]

Figure 1. Footnote in ISO/IEC 17025:2017 on ISO/IEC Guide 99:2007

Warning

It is strongly advised not to use rich-text formatting within named reference tags, as it can lead to unexpected results and problems with copy-pasting.

Numeric reference tag with automatic reference fetching

An automatically-fetched reference can be assigned a numeric reference tag, by using the same previous method with the sole difference of putting a number instead of a name.

This approach is useful when working with flavors whose reference system is named by default, such as ITU.

Example 9. Example of numeric reference tag with automatic fetching

* [[[h760,(1)ITU-T H.760]]] Recommendation ITU-T H.760 (2009), _Overview of multimedia application frameworks for IPTV services_.

* [[[x1255,(1)ITU-T X.1255]]] Recommendation ITU-T X.1255 (2013), _Framework for discovery of identity management information_.

Note	Any number can be entered between the parentheses. The references will be incrementally re-sorted according to standard drafting rules specified by the flavor during compilation.

Note	In the case of encoding bibliography items in ISO deliverables, this practice is not necessary — the reference system used in the bibliography of ISO deliverables is already numeric by default. Numeric tags do not need to be explicitly specified.

Entering bibliographic references

Automatic fetching via Relaton ("auto-fetch")

General

Relaton can fetch bibliographic entries for any standards known to have online bibliographic databases.

Any bibliographic entry recognized through its document identifier prefix will by default have its bibliographic entry fetched by the appropriate Relaton extension.

The fetched data overrides any content about the item provided in the document, since the online bibliography is treated as the source of truth for that standards document.

Standards identifier / Document identifier lookup

The format of the standard identifier required for automatic lookup is documented at Automatic reference lookup.

Note	Currently Metanorma supports auto-fetching document identifiers supported by Relaton, see here for the full list.

Example 10. Example of specifying an auto-fetched reference

The following will trigger auto-fetching:

* [[[ref1,ISO 20483]]]

and gets rendered as:

ISO 20483:2013. Cereals and cereal products — Determination of moisture content — Reference method

DOI identifier lookup

DOI identifiers are supported as auto-fetch targets [added in https://github.com/relaton/relaton-cli/releases/tag/v1.14.0] through the Crossref bibliographic information service.

This means that any book, journal article, conference paper or dataset that has a DOI and bibliographic information at Crossref can be cited by providing its DOI identifier as its bibliographic tag. Metanorma will import the bibliographic details of the reference from Relaton and format them in the required format of the current Metanorma flavour.

This is triggered by an identifier string prefixed with doi: or `DOI `, followed by the full DOI identifier.

Example 11. Example of specifying an auto-fetched DOI reference

The following will trigger auto-fetching:

* [[[ref1,doi:10.1045/november2010-massart]]]

and gets rendered as:

Massart D., Shulman E., Nicholas N., Ward N., & Bergeron F. Taming the Metadata Beast: ILOX. D-Lib Magazine Vol. 16 No. 11/12. November 2010. Available from: link:http://dx.doi.org/10.1045/november2010-massart"

ISBN identifier lookup

ISBN identifiers are supported as auto-fetch targets [added in https://github.com/relaton/relaton-cli/releases/tag/v1.14.0] through the OpenLibrary API service [added in https://github.com/relaton/relaton-cli/releases/tag/v1.17.2].

This is triggered by an identifier string prefixed with isbn: or `ISBN `, with the number following the ISBN-10 or ISBN-13 number, with or without dashes.

Example 12. Example of specifying an auto-fetched ISBN reference

The following will trigger auto-fetching:

* [[[ref1,ISBN 978-0-12-064481-0]]]

and gets rendered as:

Arvo, J. Graphics gems II. 1991. Boston, London: AP Professional.

Automatic fetching of joint publications

Metanorma recognises two types of joint publication:

Joint publications proper (or merged publications), in which the one document is considered to be published simultaneously by two different standards bodies.

In the case of ISO and IEC, there are longstanding partnerships with each other and with IEC, and this is reflected in the identifier assigned by the standards organisation (e.g. ISO/IEC DIR 1).

In other cases, the document is assigned a different identifier by each of the standards organisations involved, but it is still considered to be the same publication, and is described in a single bibliographic entry.
Dual publications, for which the publications are treated as separate bibliographic entries, listed together with phrasing like "also published as:".

In dual publications, the publications are regarded as separate activities with separate metadata, rather than a joint coordinated responsibility.

In case the partnership is not acknowledged in the document identifier (the documents are assigned two separate identifiers), the two separate bibliographic entries can still be fetched by Relaton, and brought together in the Metanorma bibliography [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.6.1].
[] merges together the two bibliographic entries fetched under CODE1 and CODE2: the bibliographic entry is that of CODE1, but the publication information of CODE2 (the publishing organisation and the distinct document identifier) are added to the entry.

Example 13. Rendering of a jointly published bibliographic item

ISO 10712 | ITU-R 232. ISO title of document. International Organization for Standardization and International Telecommunications Union.
[] treats the two bibliographic entries separately.

Example 14. Rendering of a dual-published bibliographic item

ISO 10712. ISO title of document. International Organization for Standardization. Also published as: ITU-R 232. ITU title of document. International Telecommunications Union.

Referencing from a Metanorma collection

Metanorma allows bibliographic entries to be specified for retrieval from a Metanorma collection [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.4.1].

Details on author/topics/document-format/collections#collection-cross-references This is achieved with the following syntax:

* [[[anchor,repo:(repository-name/document-entry,document-identifier)]]]

This retrieves item document-entry from repository repository-name; the document identifier "document-identifier" is retained in order for citations to remain well-formed.

By default, repo:(repository-name/document-entry) is left in the Metanorma XML as a document identifier, of type repo; it will typically be resolved in post-processing.

Note	The `repo:(…)` function is mutually exclusive to `path:(…)`, they cannot be used together.

Note	Bibliographical information about the entry is not auto-fetched via Relaton.

Referencing from Metanorma or Relaton files

Metanorma allows bibliographic entries to be specified by either relative or absolute paths [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.4.1], where a path leads to a Metanorma XML or a Relaton RXL reference file.

This is achieved with the following syntax:

* [[[anchor,path:(hyperlink,document-identifier)]]]

As with repo:() bibliographic entries, the document identifier document-identifier is retained in order for citations to remain well-formed.

If the hyperlink is local, Metanorma will look for an XML (Metanorma XML) or RXL (Relaton XML) file at the nominated location with the same filename, and read in the bibliographic metadata from there.

All citations of this entry in the document (referencing anchor) will be rendered with the hyperlink in HTML.

Note	The `path:(…)` function is mutually exclusive to `repo:(…)`, they cannot be used together.

Note	Bibliographical information about the entry is not auto-fetched via Relaton.

Entering pre-formatted references

For generic references, by default, Metanorma only supports formatted references, which are given as such in the AsciiDoc source.

Example 15. Example of a pre-formatted reference

[bibliography]
== Normative references

* [[[edge_mesh,Edge Mesh]]], Y. SAHNI, J. CAO, S. ZHANG and L. YANG.
_Edge Mesh: A New Paradigm to Enable Distributed Intelligence in Internet of Things_.
In: IEEE Access, vol. 5, pp. 16441-16458, 2017, doi: 10.1109/ACCESS.2017.2739804.

This is rendered as:

[1] Y. SAHNI, J. CAO, S. ZHANG and L. YANG. Edge Mesh: A New Paradigm to Enable Distributed Intelligence in Internet of Things. In: IEEE Access, vol. 5, pp. 16441-16458, 2017, doi: 10.1109/ACCESS.2017.2739804.

Note	The NIST flavour of Metanorma currently supports rendering of generic references, on an experimental basis. See the Automatic reference lookup topic for more details.

Annotating pre-formatted references using semantic elements

While a pre-formatted reference is not explicitly broken down into its semantic components, it may be expedient to mark up segments of the reference semantically, to provide information which is useful for parsing.

In order to generate an author-date reference, it is necessary to indicate the author surnames and publication date.

For that reason, a limited number of span categories can be used to annotate a pre-formatted reference [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.1.6].

These are not an exhaustive list of bibliographic fields, and if more detail is required (or a dynamically generated reference is to be generated), one of the following explicit bibliographic entry methods should be used instead.

The span categories supported are:

surname: Author surname.
initials: Author initials.
givenname: Author given name.
fullname: Combination of author surname and initials or given names, according to strict syntax (see below) [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.3.0]
organization: Corporate author.
surname.XXX: Contributor surname, with role XXX (e.g. editor).
initials.XXX: Contributor initials, with role XXX (e.g. editor).
givenname.XXX: Contributor given name, with role XXX (e.g. editor).
fullname.XXX: Contributor full name, with role XXX (e.g. editor).
organization.XXX: Corporate contributor, with role XXX (e.g. editor).
title: Title.
in_title: Title of containing bibliographic item. For types inbook, inproceedings, incollection, the title of the book, proceedings, collection containing the item.
in_surname, in_initials, in_givenname, in_organization: Name of contributor for containing bibliographic item

For types inbook, inproceedings, incollection, the author or more usually editor of the book, proceedings, collection containing the item.

So in_surname.editor, in_givenname.editor give the name of the editor of the book or proceedings that a paper is included in.
series: Series title. For articles, this is the journal title.
docid: Document identifier.
docid.XXX: Document identifier, of type XXX.
publisher: Publisher.
pubplace: Place of publication.
date: Date published. All dates in Metanorma are entered in ISO 8601-1:2019 YYYY-MM-DD format.
date.XXX: Date with type XXX (e.g. published, created, issued)
edition: Edition
version: Version
note: Note (can also be used for miscellaneous content)
uri: URI.
uri.XXX: URI, of type XXX.
pages: page or page range (e.g. 9, 9-11)
issue: issue or issue range (e.g. 9, 9-11)
volume: volume or volume range (e.g. 9, 9-11)
type: Document type. List of valid document types given in Relaton model — Bibitem type. The type is suppressed from rendering.

standard, book, inbook

Note

The surname must always precede the initials or given name for a given author in spans, to prevent ambiguity and confusion in parsing the reference. The rendered ordering of initials/given name and surname for the first and for subsequent names is determined by the flavour reference stylesheet. So span:surname[Fields], span:initials:[W.C.], never span:initials:[W.C.] span:surname[Fields].

Note	After the first instances of `surname` and either `initials` or `givenname`, any subsequent instances of `surname` or either `initials` or `givenname` are interpreted as belonging to a new contributor of the same role.

Note	`span:fullname[]` is intended as a convenience method to substitute `span:surname[]`, `span:initials[]`, `span:givenname[]` in a single macro. It has a strict syntax, and any special cases need to be marked up with the separate, explicit name parts instead:

The surname is a single word (space-delimited), occurring at the end. See the examples below.

span:fullname[A. D. Navarro Cortez]

surname is Cortez.

span:initials[A. D.] span:surname[Navarro Cortez]

surname is Navarro Cortez.

span:fullname[A. D. Navarro-Cortez]

surname is Navarro-Cortez.
Anything before the surname is a given name. So in span:fullnamename[J. Edgar Hoover], both J. and Edgar are processed as given names.
If everything before the surname ends in a full stop, they are all deemed initials. So in span:fullname[A. D. Navarro Cortez], A. D. are parsed as initials.

Example 16. Example encoding of a bibliographic item inline with semantic markup

* [[[A, B]]],
  span:surname[Wozniak], span:initials[S.], span:surname[Jobs], span:givenname[Steve],
    & surname:[Hoover], span:initials[J.] span:givenname[Edgar].
  span:date.issued[1991].
  span:date[1996].
  span:title[_Work_].
  In span:in_surname.editor[Gates], span:in_initials.editor[W. H] &
  span:in_organization[UNICEF],
  span:in_title[Collected Essays].
  _span:series[Bibliographers Anonymous]._
  span:docid.ISO[ISO 1234].
  span:pubplace[Geneva]:
  span:publisher[International Standardization Organization].
  span:uri.citation[http://www.example.com].
  vol. span:volume[5],
  pp. span:pages[2-21]
  span:type[inbook]

Note the distinction in the example between Wozniak and Jobs (authors of the paper), and Gates and UNICEF (editors of the book including the paper). Similarly, note the distinction between the title of the paper (Work), and the title of the book including the paper (Collected Essays).

After the first instances of surname and either initials or givenname, any subsequent instance of surname is interpreted as belonging to a new contributor of the same role.

Any given names and surnames MUST follow the surname that they relate to. If the names are ordered differently between the first and subsequent name, e.g. Wozniak, S. & Steve Jobs, that will be taken care of in rendering: they cannot be annotated in that way.

Note	For presentations, `title` is the title of the presentation `series` is the title of the conference `organization.distributor` is the organizer of the conference

Important

The rendering of different bibliographic types is quite different in the various stylesheets that SDOs follow, and strange things will happen if Metanorma gets the bibliographic type wrong.

Under Metanorma, the default bibliographic type is standard, and most SDOs render standards in bibliographies with very little data (no author, no publisher, no date outside of the document identifier, and so on).

If you use this notation to enter any document other than a standard, you must specify the type of document, using span:type[].

Last access date auto-retrieval and override

Metanorma supports auto-retrieval of URLs in order to set the "last accessed" date for a bibliographic item with URL.

This is performed through the relaton-render gem, where the URLs in the reference will be tried for access, and Metanorma styles the result to align to the flavour’s bibliographical stylesheet.

Append span:date.accessed[2020-01-01] at the end of the reference.

If your flavour requires date last accessed to be supplied for references with URLs, you should use date.accessed[…] to do so.

If you do not do so, Metanorma will try to access the URLs in the reference automatically.

If the URI is not accessible, no date last accessed will be given.

Typically, SDO expectation is that authors should provide dates last accessed for references they have reviewed themselves.

Overriding auto-fetched reference fields

The bibliographic span:…[] notation can be used to emend bibliographic entries fetched through Relaton [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.3.4].

Note	This is particularly important for DOI auto-fetched information, as the Crossref records are of variable quality, and often lack crucial information for citations.

Data encoded in the title following the bibliographic anchor with span:[] is used to supplement auto-fetched information.
If the span information presents information absent in the fetched record, it is added to the record.
If the span information presents information corresponding in the fetched record, it overwrites it.
Information is broken down by type:
- If an identifier, or URI, or date is of a given type, it overwrites only identifiers of the same type in the fetched record (e.g. span:docid.BSI[BSI EN 8000], span:date.published[2010]).
- The same applies to contributors: contributors of a given type overwrite only contributors of the same type in the fetched record.
- For document identifiers, you will need the type of the SDO issuing the document, which is typically the standard organization abbreviation. Look at the Semantic XML of the document for the currently fetched document, to make sure.
Information is replaced, not additive.

If there are multiple authors in the fetched record, they are replaced by the listing of multiple authors in the bibliographic spans.

To illustrate, the following citation modifies the record fetched from Crossref.

Metanorma bibliographic entry with DOI identifier fetch and data override

* [[[ref1,doi:10.1045/november2010-massart]]],
  span:surname.author[Johnson], span:givenname.author[Boris],
  span:pages[8-10],
  span:date.published[2021]

The modifications are:

The pages span are added to the source record, which contains volume and issue information, but no page information.
The authors listed for the source record are overwritten by the single author "Boris Johnson".
The date published is overwritten by the new date 2021. The date the article was issued, by contrast, is left alone.

Importing bibliographic records from other formats

Metanorma can import files containing bibliographic records in other formats [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.2.9]. To date, only Bibtex is supported.

In order to specify an external Bibtex file, use the relaton-data-source document attribute:

:relaton-data-source: path/to/bibtex-file

In order to specify multiple external Bibtex files, use relaton-data-source-{id} document attributes, where the value of {id} is the source identifier used to differentiate each import file:

:relaton-data-source-bib1: path/to/first/bibtex-file
:relaton-data-source-bib2: path/to/second/bibtex-file

References to a bibliographic item imported this way are expressed in the bibliography with the bibliographic anchor local-file(SOURCE, KEY), where SOURCE is the name of the source identifier for the import file, and KEY is the identifier of the reference in the import file. So given the import statements above,

== Bibliography
* [[[ref1, local-file(bib1, tc211)]]]

will import the reference inside the Bibtex file path/to/first/bibtex-file (the value of relaton-data-source-bib1) that starts as e.g.

@book{tc211
  ...
}

If only one file was imported through relaton-data-source, the source identifier is omitted (or else "default" is used):

== Bibliography
* [[[ref1, local-file(tc211)]]]

Entering with AsciiBib

Bibliographic entries can be entered in the AsciiBib format.

AsciiBib is a bibliography entry format that uses AsciiDoc definition lists to capture the structure of Relaton XML.

This approach is documented in relaton.org.

Example 17. Example of entering an entry using AsciiBib (ISO 123) with an AsciiBib ID

[bibliography]
== Normative references

[%bibitem]
=== Rubber latex -- Sampling
id:: iso123
docid::
type::: ISO
id::: ISO 123
docid::
type::: ABC
id::: 32784
type:: standard

The id attribute of %bibitem clauses (the anchor of the clause) can be overridden by a Metanorma AsciiDoc anchor on the clause [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.6.1].

This can be required for Metanorma AsciiDoc to process cross-references correctly.

Note	Metanorma AsciiDoc anchors must not be preceded by `_`, as Metanorma AsciiDoc uses that to indicate anchors it inserts automatically, which are not supplied in the source.

Example 18. Example of entering an entry using AsciiBib (ISO 123) with an AsciiDoc anchor

[bibliography]
== Normative references

[[iso123]]
[%bibitem]
=== Rubber latex -- Sampling
id:: iso123
docid::
type::: ISO
id::: ISO 123
docid::
type::: ABC
id::: 32784
type:: standard

Suppressing display

It is expected that if a citation is made in the main body of the document, its corresponding reference will be included in the bibliography. It is however possible to suppress display of that reference in the bibliography, by wrapping it in hidden() [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.11.4].

[bibliography]
== Bibliography

* [[[ref1,hidden(ISO 639-1)]]], ISO 639-1.
* [[[ref2,ISO 639-2]]], ISO 639-2.

Entering with Relaton XML (EXPERT only)

Warning

This functionality is strongly discouraged due to the ease of breaking the resulting Metanorma XML. It is useful only for limited use cases and only intended for experts.

Bibliographic entries can also be given as raw Relaton XML, in an AsciiDoc passthrough block.

Of course, any Relaton XML BibItem entries need to be valid, and using correct id attributes.

Example 19. Example of entering an entry using Relaton XML (ISO 1)

[bibliography]
== Normative references

++++
<bibitem id="doc1">
<docidentifier>ISO 1</docidentifier>
<title>Geometrical product specifications (GPS) -- Standard reference temperature for the specification of geometrical and dimensional properties</title>
</bibitem>
++++

Citations and localities

General

Citations of references in Metanorma are formulated as cross-references.

The anchor cross-referenced is the internal identifier given for the bibliographic entry.

Example 20. Example of specifying a reference anchor (ref1 is the anchor)

<<ref1,part=IV,chapter=3,paragraph=12>>

Metanorma AsciiDoc works in a similar way to typical AsciiDoc: any text in a cross-reference that follows a comma constitutes custom text for the cross-reference.

A cross-reference <<ISO7301,the foregoing reference>> will be rendered as “the foregoing reference”, and hyperlinked to the ISO7301 reference.

Localities

General

Citations can include details of where in the document the citation is located.

These localities are entered by suffixing the lowercase type of locality, then an equals sign, then the locality value or range of values.

Multiple instances of locality and reference can be provided, delimited by comma or colon.

The references cannot contain spaces. Any text following the sequence of localities will be displayed instead of the localities.

Locality types

The following locality types are recognised in Metanorma:

section: a general section
clause: a clause
part: a document part
paragraph: a paragraph
chapter: a chapter
page: a page
line: a line identified by the line number
table: a table
annex: an annex
figure: a figure
example: an example
note: a note
formula: a mathematical formula
list: a list
time: a particular time
anchor: an anchor
whole: whole
title: the title

Except for the locality types of whole and title, all locality types require explicit specification of an identifier to make sense.

Example 21. Example locality types that are used on their own

whole
title

Example 22. Example locality types that need to be used with identifiers

note 1 (or note=1)
page 77-99 (or page="77-79")
annex A (or annex=A)
line 399 (or line=399)

Locality types not listed here shall be entered using the mechanism described at Custom locality.

Simple locality

A simple locality is specified with a unique location identifier or free text.

Example 23. Example of referencing locality in Metanorma citations

<<ISO7301,clause=3.1-3.4>>

NOTE: This table is based on <<ISO7301,table=1>>.

Sampling shall be carried out in accordance with <<xxx,section="5-3-1,bis">>

Example 24. Example that renders a reference as free text

// renders as: "the foregoing reference"
<<ISO712,the foregoing reference>>

To refer to the “whole” item, or the title within a block, the corresponding keyword is used (whole, title), without an argument.

Example 25. Example of referencing with a "whole" locality

// renders as: "ISO 712, Whole of text"
<<ISO712,whole>>

Hierarchical locality

A hierarchical location is specified through consecutive narrower localities.

Example 26. Example of referencing a hierarchical locality

// renders as "`Part IV, Chapter 3, paragraph 12`"
<<ref1,part=IV,chapter=3,paragraph=12>>

Example 27. Example that renders the reference with (multiple) hierarchical localities

// renders as: "ISO 712, Section 5, Page 8-10"
<<ISO712,section=5, page 8-10>>

Example 28. Example of referencing locality with additional text

// renders as "ISO 712, 5:8-10"
// ("5:8-10" treated as replacement text for all the foregoing)
<<ISO712,section=5, page=8-10: 5:8-10>>

Discontinuous locality

Discontinuous localities can be named by repeating the same locality type.

Example 29. Example of referencing a discontinuous locality

// renders as "`page 4, page 7`"
<<ref1,page=4,page=7>>

Discontinuous localities can also be specified by delimiting sequences of localities with semicolon [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.3.24]

Example 30. Example of referencing discontinuous hierarchical localities

// renders as "`Part IV, Chapter 3; Part VI, Chapter 9`"
<<ref1,part=IV,chapter=3;part=VI,chapter=9>>

Complex locality

Complex relations between discontinuous references can be specified by prefixing conjoining verbs to sequences of localities separated by semicolon [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.0.4].

This will result in overt connectives between the references, which will be internationalised.

Conjoining verbs include:

and!
or!
from!
to!

Example 31. Example of referencing a complex locality

// renders as: "`Chapters 3 and 7`"
<<chapter=3;and!chapter=7>>

Example 32. Example of referencing a complex locality that contains a hierarchical locality

// renders as: "Part IV, Chapter 3 or Part VI, Chapter 9"
<<ref1,part=IV,chapter=3;or!part=VI,chapter=9>>

Note	This is similar to the behavior in Combination of cross-references.

As with cross-references, more than two references combined by “and” should be marked up with semicolons. Internationalisation during rendering will take care of separating the references by colon, and inserting any necessary conjunction wording (“and”).

Example 33. Example of referencing multiple references that are complex localities

<<ref1,clause=3.2;clause=4.7;clause=4.9;clause=9>>
// or
<<ref1,clause=3.2;and!clause=4.7;and!clause=4.9;and!clause=9>>

Note

If references are joined with semicolons and connectives, but the locality is not supplied for a cross-reference, it is filled in by referring to the preceding conjoined cross-reference [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.8.0]. For example, clause=3.2;and!4.7;to!4.9;and!9 is corrected internally to the more explicit clause=3.2;and!clause=4.7;to!clause=4.9;and!clause=9.

Trailing text after the sequence of locality=reference (or locality{space}reference) is treated as custom text for the cross-reference, as would occur normally in a typical cross-reference.

The locality can appear in quotations if it contains special characters (like dashes or commas).

Custom locality

Locality types not listed in Locality types are entered using the "custom locality" functionality.

Metanorma accepts a fixed list of locality types in cross-references (see Locality types), which is not meant to be exhaustive of all possible locality types.

annex is recognized as a generic reference to annexes in documents, but it does not recognize appendixes (instead of annexes), or as distinct from annexes (as is the case in ISO deliverables).

A custom locality is entered by prefixing the locality type with locality:.

A custom locality has the following properties:

The locality type will be rendered as text preceding the equal sign.
The locality type shall not contain commas, colons, or space.
The locality type is meant to be valid for all languages.

Note
The custom locality locality:appendix would be used for both English and French texts.
Localization of custom locality types is managed through inclusion in the internationalization YAML file for that language, which has to be customized as part of the Metanorma flavor implementation.

Note
The custom locality locality:appendix is realized as French Appendice through configuration in the Metanorma flavor implementation.

Example 34. Example of referencing a custom locality the locality: prefix

This encoding:

<<ISO-IEC_DIR_1_ISO_SUP,annex=SL,locality:appendix=2,clause=3.2>>

Renders as:

"ISO/IEC DIR 2, Annex SL, Appendix 2, Clause 3.2"

Locality plus custom text

Any text after the bibliographic localities is still treated as custom cross-reference text.

As with references without localities, the custom cross-reference text is the only text that is displayed in the document; but the cross-reference still captures the specific locality of the reference, e.g. for cross-reference generation.

Example 35. Example of referencing with bibliographic localities with additional custom text

<<ISO7301,clause=5,table=1,the foregoing reference>>

rendered as:

the foregoing reference

Anchor locality

Exceptionally, the anchor locality is only used in HTML, to generate anchor links to other HTML pages [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.4.1].

It is intended for use with bibliographic anchors linking to URLs (repo:(), path:()): see Referencing from a Metanorma collection and Referencing from Metanorma or Relaton files.

Example 36. Example of using the anchor locality for rendering in HTML output

The following input:

<<ISO7301,clause=2,table=1a,page=7-9,anchor=xyz>>

...

* [[[ISO7301,path:(./iso7301.html,ISO 7301)]]]

will render in HTML as:

<a href="./iso7301.html#xyz">ISO 7301, Clause 2, Table 1a, page 7-9</a>

Case and dropped locality labels

The capital%, lowercase% and droploc% options used for internal cross-references can also be used as prefixes to localities, modifying how those localities are rendered [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.8.9].

Example 37. Example of using droploc in a citation locality

// renders as "ISO 7301, 2"
<<ISO7301,droploc%clause=2>>

Example 38. Example of using lowercase in a citation locality

// renders as "ISO 7301, clause 2"
<<ISO7301,lowercase%clause=2>>

Styled cross-references

As with internal cross-references, cross-referenced citations can have a style attribute [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.4.4]. As of this writing, the only values allowed are the types of docidentifier value that can be substituted for the primary identifier of the reference, for standards documents; those values will need to be looked up in Relaton (and the Semantic XML of the document). For example, given the citation

<bibitem type="standard" id="bib1">
...
<docidentifier type="ISO" primary="true">ISO/FDIS 17664-1</docidentifier>
<docidentifier type="URN">urn:iso:std:iso-fdis:17664:-1:ed-1:fr</docidentifier>
...
</bibitem>

A crossreference [bib1] will be populated by default with the primary or else the first docidentifier value found, ISO/FDIS 17664-1. However, given style=URN%, the first docidentifier value of type URN will be sought instead, and the cross-reference will be populated by default as URN urn:iso:std:iso-fdis:17664:-1:ed-1:fr.

Link-only references

A standards document can be cross-referenced in Metanorma without that document appearing in the document references.

Such cross-reference is treated as equivalent to a cross-reference to a hidden citation, as documented in Hiding citations with hidden().

Link-only references can be added to Metanorma AsciiDoc using the following command:

++std-link:[...]++

Where the std-link command contains the same text as a normal cross-reference to a standard, including localities and other directives. There is no need for an explicit bibliographic entry. [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.0.4].

The following two examples are equivalent:

Example 39. Link-only reference of ISO 123 using std-link

std-link:[ISO 123,droploc%clause=3]

Example 40. Link-only reference of ISO 123 using a hidden citation

<<ref1,droploc%clause=3>>

[bibliography]
== Bibliography

* [[[ref1,hidden(ISO 123)]]]

Combination of citations

Simple citations can be combined with connectives, in a similar fashion to cross-references (Combination of cross-references), and which will be internationalised as appropriate [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.2.7].

Example 41. Example of rendering a range of citations

The following citation range:

<<from!context;to!improvement>>

is rendered as:

From [3] to [7]

Reference processing flags

General

Various processing flags can be entered at the document identifier element to specify different reference processing behaviour. All such flags are optional.

Reference processing flags need to be entered according to the following pattern (in this order):

[[[{anchor},nofetch(hidden(dropid({document identifier or reference tag})))]]]

nofetch(): Disable automatic lookup of references. See Disable auto-fetch with nofetch()
hidden(): Do not show this item in the bibliography. See Hiding citations with hidden().
dropid(): Do not display the document identifier. See Ignoring document identifiers with dropid().

Note	The `repo:()` and `path:()` functions are to be entered as document identifiers in this pattern.

Disable auto-fetch with `nofetch()`

See Automatic reference lookup: Disabling automatic lookup.

Ignoring document identifiers with `dropid()`

The document identifier is critical to formulating both citations and bibliographies. There are times, however, where the supplied document identifier is to be ignored in bibliographies.

When a manual bibliographic item is entered (not auto-fetched), with a user-defined anchor and the document identifier in triple brackets, followed by bibliographic details provided as text.

In this case, the bibliographic item is rendered with the document identifier placed in brackets after the provided bibliographic details, as it is shown in Example of a manually-entered bibliographic item with document identifier shown after bibliographic details.

Example 42. Example of a manually-entered bibliographic item with document identifier shown after bibliographic details

* [[[id1,ELOT 743]]], _Transliteration of Greek into Roman script._

Notice that the document identifier is placed in brackets after the provided bibliographic details:

There are situations where it is useful to suppress the document identifier in the bibliography, for example:

the bibliographic item is not a standard, so the identifier should not be used;
there is no authoritative form for the document identifier for this bibliographic item.

The dropid() [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.1.4] citation processing flag can be used to suppress the appearance of the document identifier in the bibliography.

Example 43. Example of using dropid(…) to drop rendering of a document identifier in the bibliography

* [[[id1,dropid(GIBBON)]]], Gibbon, Edward. 1776-1789. _Decline and fall of the Roman Empire._ London: Strahan & Cadell.

The resulting rendering omits the document identifier:

[1] Gibbon, Edward. 1776-1789. Decline and fall of the Roman Empire. London: Strahan & Cadell.

Hiding citations with `hidden()`

It is possible to add a citation to a document while suppressing its rendering in all rendered outputs.

This is done so that the Metanorma Semantic XML will still contain information about the citation, and can use it, for instance, to populate cross-references to that document.

A hidden citation can be added to a Metanorma document by wrapping the reference tag in hidden(…). [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.0.0]

Example 44. Example of hiding a named reference (ISO 8601-1:2019)

The following encoding will hide the particular bibliographic reference.

[bibliography]
== Normative references

* [[[iso86011,hidden(ISO 8601-1:2019)]]]

CSV notation

The notation shown up to this point for reference processing flags has the potential of being too complicated to parse, if deeply nested or if the parentheses of flags are combined with the parentheses of user-supplied labels or of "all parts".

For that reason, an alternative notation is supported, involving key/value pairs delimited by comma and equals signs in the anchor label [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v2.4.4].

For example, the following two references are equivalent:

[bibliography]
== Normative references

* [[[iso8601_1,nofetch((Date-Time)ISO 8601-1:2019)]]], _Date and time — Representations for information interchange — Part 1: Basic rules_
* [[[iso8601_1a,nofetch=true,usrlabel=Date-Time,code=ISO 8601-1:2019]]], _Date and time — Representations for information interchange — Part 1: Basic rules_

The CSV-based notation has the following keys:

nofetch: true|false
hidden: true|false
dropid: true|false
local-file: (filename of local Relaton cache)
repo: (repository name)/(document entry)
path: (file path)
number: (number, for a numeric ID of a citation)
usrlabel: (user-supplied label of reference)
code: (authoritative identifier of reference)

If no key is supplied in the CSV entry, it is assumed to be a code; e.g. nofetch=true,usrlabel=Date-Time,ISO 8601-1:2019 is interpreted as nofetch=true,usrlabel=Date-Time,code=ISO 8601-1:2019.

General

Numbering and ordering

Predefined text

Entering individual references

General

Types of references

Reference tags

Implied reference tags

Overriding fetching

Numeric reference tags

Named reference tags

General

Named reference tag with fully specified bibliographic entry

Named reference tag with automatic reference fetching

Numeric reference tag with automatic reference fetching

Entering bibliographic references

Automatic fetching via Relaton ("auto-fetch")

General

Standards identifier / Document identifier lookup

DOI identifier lookup

ISBN identifier lookup

Automatic fetching of joint publications

Referencing from a Metanorma collection

Referencing from Metanorma or Relaton files

Entering pre-formatted references

Annotating pre-formatted references using semantic elements

Last access date auto-retrieval and override

Overriding auto-fetched reference fields

Importing bibliographic records from other formats

Entering with AsciiBib

Suppressing display

Entering with Relaton XML (EXPERT only)

Citations and localities

General

Localities

General

Locality types

Simple locality

Hierarchical locality

Discontinuous locality

Complex locality

Custom locality

Locality plus custom text

Anchor locality

Case and dropped locality labels

Styled cross-references

Link-only references

Combination of citations

Reference processing flags

General

Disable auto-fetch with nofetch()

Ignoring document identifiers with dropid()

Hiding citations with hidden()

CSV notation

Disable auto-fetch with `nofetch()`

Ignoring document identifiers with `dropid()`

Hiding citations with `hidden()`