object-id-type Object Identifier Type (in Related Object)

Type of object identifier (for example, an XML ID, a string, the label of the object, a DOI) for a <related-object> element.
OPTIONAL on element: <related-object>
Value Meaning
Text, numbers, or special characters The type of the identifier, for example, “ID” for an XML attribute of type ID.
Restriction This is an optional attribute; there is no default.