It is possible to extract sections out of an article. When this is done, and the section becomes a complete XML document in its own rright, it is useful for this document to contain information that identifies its origins.

DOIs are encouraged to help identify components of an article. The format for the article DOI as it appears in the XML is as follows:

doi="10.1081/ADA-123456789"

Similarly, the format for component identifiers will follow the similar rules of syntax:

However, each section can also contain the identifier for the entire article (in the "articleid" attribute).