Metanorma: Aequitate Verum

References and bibliography

General

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

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 3 (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 3 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 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 note of type “boilerplate” [added in https://github.com/metanorma/metanorma-standoc/releases/tag/v1.9.2]:

== Normative references

[NOTE,type=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:

The basic form of a reference is a "pre-formatted reference", which relies on the user to supply a formatted reference. Details of that format are available at Entering pre-formatted citations.

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

If automatic fetching is not available for the reference, and if machine-readability or accurate rendering is important, [asciibib] is the best method for entering structured and detailed bibliographic information within a document.

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")).

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]]]
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 8. 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")

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.

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

Note
Currently Metanorma supports auto-fetching document identifiers from: ISO, IEC, IETF, GB, NIST, OGC, CalConnect and many more.
Example 9. 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

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.

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 citations

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

Example 10. Example of a pre-formatted citation
[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.

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 11. 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 12. 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

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 13. 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 14. 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 15. Example locality types that are used on their own
  • whole

  • title

Example 16. 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 17. 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 18. 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 19. 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 20. Example of referencing a hierarchical locality
// renders as "`Part IV, Chapter 3, paragraph 12`"
<<ref1,part=IV,chapter=3,paragraph=12>>
Example 21. 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 22. 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 23. 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 24. 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 25. Example of referencing a complex locality
// renders as: "`Chapters 3 and 7`"
<<chapter=3;and!chapter=7>>
Example 26. 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 27. 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>>

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

Metanorma accepts a fixed list of locality types in cross-references (see Locality types). This list is not exhaustive of all possible locality types.

For example, "annex" is recognized as a generic reference to annexes in documents. It does not recognize appendixes (instead of annexes), or as distinct from annexes (as is the case in ISO).

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

Custom localities are entered by prefixing the locality type with the string locality:. The locality type will be rendered as text preceding the equal sign. The locality type is meant to be valid for all languages, and is localised as with other localities through inclusion in the internationalisation YAML file for that language. (So locality:appendix would be used for both English and French texts; the realisation of locality:appendix as French Appendice is a matter of gem configuration.)

Example 28. 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"

Custom localities may not contain commas, colons, or space.

Localities with the locality: prefix can be recognized in internationalization configuration files, but they need to be added as part of the flavour..

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 29. 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 30. 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 31. Example of using droploc in a citation locality
// renders as "ISO 7301, 2"
<<ISO7301,droploc%clause=2>>
Example 32. Example of using lowercase in a citation locality
// renders as "ISO 7301, clause 2"
<<ISO7301,lowercase%clause=2>>

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 33. Link-only reference of ISO 123 using std-link
std-link:[ISO 123,droploc%clause=3]
Example 34. Link-only reference of ISO 123 using a hidden citation
<<ref1,droploc%clause=3>>

[bibliography]
== Bibliography

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

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()

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 35. 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 36. 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 37. 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)]]]