Value MUST be part of code list 'Mime code (IANA Subset)'.
/ubl:Catalogue/cac:CatalogueLine/cac:Item/cac:ItemSpecificationDocumentReference/cac:Attachment/cbc:EmbeddedDocumentBinaryObject
not(@mimeCode) or (some $code in $clMimeCode satisfies $code = @mimeCode)