There has been a discussion on the METS list about the different
versions of the xlink schema that are being used with METS, MODS and EAD:
EAD refers to
METS refers to
MODS refers to

This results in validation errors when trying to combine, say EAD and
METS. It is desirable to use one version in all of these.

We have placed a copy of the METS xlink schema at:

The new version of MODS (Ver 3.3) will import from that address. 

Daniel Pitti is working on altering the EAD schema towards the end of
using the xlink schema cited above rather than the EAD xlink schema used

^^  Rebecca S. Guenther                                   ^^
^^  Senior Networking and Standards Specialist            ^^
^^  Network Development and MARC Standards Office         ^^
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