Name or identifier of an entire journal issue (for example, a DOI).
External Identifier: This element holds an external identifier, typically assigned to an article by a publisher. 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.
<!ELEMENT issue-id (#PCDATA) >
Text, numbers, or special characters
No sample is available at this time.