Message

Attribute 'listID' MUST contain value 'ReferencesTypeCodes'

Context
/espd-req:ESPDRequest/cac:AdditionalDocumentReference/cbc:DocumentTypeCode
Test
not(@listID) or @listID = 'ReferencesTypeCodes'
Usage
/ espd-req:ESPDRequest / cac:AdditionalDocumentReference / cbc:DocumentTypeCode / @listID