Dear Rebecca,

We widely use @xlink:href on <relatedItem> for linking to host records, in the manner of 

<relatedItem type="host" xlink:href="#uuid-589defe4-b2a5-4873-926e-8fb2b91e5078">
            <detail type="volume">
            <detail type="issue">
            <extent unit="pages">
            <date encoding="w3cdtf">1994</date>

The record with the @ID "uuid-589defe4-b2a5-4873-926e-8fb2b91e5078" holds the host record, here a periodical.

Strangely, in VRA, @href does not occur in the xlink namespace.



On 04 Dec 2013, at 19:16, Guenther, Rebecca <[log in to unmask]> wrote:

MODS has the attribute xlink on a number of elements to provide an external link.  Although the XML schema specification has a further breakdown for different types of xlinks, at this time, only xlink:href is defined for MODS.
Example from guidelines: <abstract xlink:href= ""/>
Xlink hasn't been implemented widely in the community partially because the W3C hasn't provided much guidance. METS and MODS have both adapted xlink and made up their own xlink schemas with subtle differences-- which has caused conflicts.
Who in the MODS community actively use xlink? Is there an alternative for linking that might be considered? MODS uses authorityURI and valueURI when linking to external authority systems and controlled values. For the example above (abstract linking to an external resource) is there another way this can be done?
Rebecca S. Guenther
Network Development & MARC Standards Office
Library of Congress
Washington, DC 20540