6591c9e4_rel_values___Microformats_Wiki___specification_where_possible_
[Keyword] alternate [Effect on link] external resource [Effect on a, area] external relation HTML4 Link types
Designates substitute versions for the document in which the link occurs. When used together with the lang attribute, it implies a translated version of the document. When used together with the media attribute, it implies a version designed for a different medium (or media).
existing rel values · Microformats Wiki
Brief description (from the relevant specification where possible)