restoring the vCard link

Author: domel

spec/index.html

@@ -4582,7 +4582,7 @@ <h4>Descriptions of Resources</h4>
             </div>
           </div>
           <p>which includes the blank node closure for the 
-            vCard vocabulary <code>vcard:N</code>.
+            <a data-cite="vcard-rdf#" class="inform">vCard vocabulary</a> <code>vcard:N</code>.
             Other possible mechanisms for deciding what
             information to return include Concise Bounded Descriptions [[CBD]].</p>
           <p>For a vocabulary such as FOAF, where the resources are typically blank nodes, returning