Message

Value MUST be part of code list 'ISO 639-1 Language Codes'.

Context
/espd-req:ESPDRequest/ccv:Criterion/ccv:LegislationReference
Test
not(@langID) or (some $code in $clespd-LanguageCodeEU satisfies $code = @langID)
Code lists
ISO 639-1 Language Codes
Usage
/ espd-req:ESPDRequest / ccv:Criterion / ccv:LegislationReference / @langID