Message

DocumentReference Identifier for a Call for Tender Reference MUST be expressed in a UUID syntax (RFC 4122)

Context
ubl:Tender/cac:DocumentReference[normalize-space(./cbc:DocumentTypeCode)='311']/cbc:ID
Test
matches(normalize-space(.),'^[a-fA-F0-9]{8}(\-[a-fA-F0-9]{4}){3}\-[a-fA-F0-9]{12}$')
Usage
/ t005:Tender / cac:DocumentReference / cbc:ID