Positive identification of the reference such as a unique identifier.

Cardinality
1..1
Namespace
cbc urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2
Data type
Document reference
Business terms
tir01-019
Rules
Identifier/Error message Flag
EHF-P09-CHA-B03201
Document MUST NOT contain elements not part of the data model.
fatal