Holdings XML Schemas for ES B1 & B2

The ZIG XML Holdings Schema v7 has been updated to more accurately reflect
attribute enumerations etc. as specified in Holdings Abstract Schema.

I have also prepared derived XML Schemas corresponding to those two Abstract
Schema Element Sets (B-1 and B-2), which are referenced in the ONE-2
Profile.

Links to the schemas etc, are found at the "usual" location, which is
referenced from the Z39.50 Maintenance Agency Web:
http://lcweb.loc.gov/z3950/agency/defns/holdings.html
http://www.portia.dk/zholdings/

By reference to the Element Set XML Schemas it is possible to validate
instances of B-1 and B-2 Holdings XML Structures. 
Perhaps these Element Set XML Schemas can serve as templates for
specification of other Element Sets derived from the Base XML Holdings
Schema.

Best regards,
Poul Henrik Jørgensen, DBC