Type of Publication Identifier


Names the type of identifier, or the organization or system that defined the identifier, for a journal article identifier (part of the article metadata) or for a publication cited in a bibliographic reference list.


Used on the <article-id> element, which holds an identifier for the entire article. Also used on the <pub-id> element, which is an identifier for a publication cited in a bibliographic reference <citation>.

Attribute Values

In Elements

<article-id> Article Identifier
<pub-id> Publication Identifier for a Cited Publication
Value Meaning
coden Obsolete PDB/CCDC identifier, which may be present on older articles.
doi Digital Object Identifier.
medline NLM MEDLINE identifier.
pii Publisher Item Identifier; see /epub/piius.htm
pmid PubMed ID; see query.fcgi?db=PubMed
publisher-id Identifier (ID) such as an “article-id”, “artnum”, “identifier”, “article-number”, etc. that is given to an article by the publisher of the article. This could be the publisher’s unique internal production number or a more general identifier.
sici Serial Item and Contribution Identifier. (A journal article may have more than one SICI, i.e., one for a print version and another for an electronic version.)
other Something other than one of the identifiers named in the list just given.
Restriction: This attribute may be specified if the element is used.