UBL 2.1 Standard (November 2013)
A library of over 2,000 XML components together with 65 business document schemas.
Online hub document: http://docs.oasis-open.org/ubl/os-UBL-2.1/UBL-2.1.html
Offline package (with schemas): http://docs.oasis-open.org/ubl/os-UBL-2.1/UBL-2.1.zip
UBL 2.0 Standard (December 2006)
A library of over a thousand XML components together with 31 business document schemas.
Errata for UBL 2.0
OASIS UBL 2.0 Update Package
UBL 1.0 Standard (November 2004)
A library of over 600 XML components together with eight business document schemas and a wealth of support files.
UBL 1.0 Legacy materials
Links to the UBL 1.0 Naming and Design Rules, International Data Dictionary, Small Business Subset, and UBL Formatters can be found on the Legacy Support page: