<link> defines an association or hypertextual link among elements or passages, of some type not more precisely specifiable by other elements. [16.1 Links]
This element should only be used to encode associations not otherwise provided for by more specific elements.
The location of this element within a document has no significance, unless it is included within a linkGrp, in which case it may inherit the value of the type attribute from the value given on the linkGrp.