customization guidelines example

From today's discussion, an example of approach and guidelines for 
customization (conformance, compatibility, extension, versioning, 
subsetting, ...)

http://docs.oasis-open.org/ubl/guidelines/UBL2-Customization1prd03.pdf

from http://lists.oasis-open.org/archives/ubl/200912/msg00009.html

UBL is an implementation of the ebXML Core Component Technical 
Specification.

-Anne