1. UBL 2.1 developed by the Organization for the Advancement of Structured Information Standards is a royalty-free library of standard electronic Extensible Markup Language (XML) business documents.

Der von OASIS (Organization for the Advancement of Structured Information Standards) entwickelte Standard UBL 2.1 ist eine gebührenfreie Library von elektronischen Standard-Geschäftsdokumenten im XML-Format (Extensible Markup Language).