best practice property to use for naming a skos:ConceptScheme

Yesterday I was discussing with a colleague whether rdfs:label or 
skos:prefLabel would be better, and today I noticed this at 
http://www.w3.org/TR/2009/REC-skos-reference-20090818/#L1045 :

<S>  rdf:type skos:ConceptScheme ;
   dct:title "My First Thesaurus" ;
   skos:hasTopConcept<B>  .

dct: is never declared anywhere. I'm guessing from the t that 
http://purl.org/dc/terms/ was meant, but title is a property of 
http://purl.org/dc/elements/1.1/ , not of http://purl.org/dc/terms/ . 
Either way, it's confusing and another example of why people should 
always declare their prefixes, if only in a note at the beginning of a 
spec that uses them in examples.

But enough of my complaining. Has anyone seen a common practice using a 
particular property to assign a human-readable label to a 
skos:ConceptScheme?

thanks,

Bob