Unique external identifier assigned to an article.
Multiple Identifiers: There may be many identifiers for a single article, and each <article-id> holds only one. While such an identifier may be a unique identifier in some system, an article can be identified in many systems. The content for this element may be assigned by a publisher, a jobber, Crossref, or PubMed Central, for example. Examples of such identifiers include the publisher’s tracking number, a DOI, a PNAS number, etc.
Attribute Best Practice
Type of Identifier Best Practice: Best Practice is to use the @pub-id-type attribute to indicate the type of the external identifier, such as a publisher’s identifier, a DOI, a PMID, an aggregator’s or archive’s identifier, the identifier assigned by an indexing or hosting service, or similar. (See @pub-id-type for values.)
Authority for Identifier Best Practice: The attribute @assigning-authority should name the organization or system that assigned the identifier or administers the identifier (such as Crossref, OCLC, GenBank, Figshare).
Historical Note: Until JATS version 1.2d2 (2018), the @contrib-id-type’s value conflated two meanings: the attribute could hold the type of identifier (such as an ORCID or a arXiv Identifier), or it could hold the name of the organization or system that defined or registered the identifier (such as ORCID or Elsevier). There was no way to state both that the identifier content of the element was a Scopus Identifier and that the administrator was Elsevier. Although all the previous @contrib-id-type values will continue to be accepted, for Best Practice, the @assigning-authority should name an organization and the @pub-id-type attribute should describe the identifier type.
External Identifier: The <article-id> element holds an external identifier, typically assigned to a document by an agency such as the publisher, an archive, an aggregator or hosting service, or Crossref or other DOI authority. The contents of this element should not be confused with the @id attribute, which holds an internal document identifier that can be used by software to preform a simple link inside the document.
Conversion Note: An archive may attempt to carry all the identifiers associated with an article. For example, during conversion PubMed Central will create <article-id>s for identifiers that come from the publisher as elements or as attributes on the original article.
<!ELEMENT article-id (#PCDATA) >
Text, numbers, or special characters
There can be many <article-id>s of different types:
<article dtd-version="1.2"> <front> <journal-meta>...</journal-meta> <article-meta> <article-id pub-id-type="publisher-id">1037</article-id> <article-id pub-id-type="doi">10.1128/JCM.39.7.2634-2636.2001</article-id> <article-id pub-id-type="pmid">11427581</article-id> <article-categories>...</article-categories> <title-group> <article-title>Molecular Identification of a <italic>Dietzia maris</italic> Hip Prosthesis Infection Isolate</article-title> </title-group> ... </article-meta> </front> ... </article>
The Mathematical Reviews (MR) article identifier:
... <article-meta> <article-id assigning-authority="mr" pub-id-type="publisher-id">1707243</article-id> ... </article-meta> ...
The Zentralblatt MATH (zbMATH) article identifier:
... <article-meta> <article-id pub-id-type="zbl">06451297</article-id> ... </article-meta> ...