Relation rdfs#label (?,pm#string)  in WebKB, with FO, use the link '_'
  supertype:  pm#name (pm)
  equal:  daml#label
  subtype:  dl#name (dl#entity,rdfs#Literal)  a relation between an instance of a concept and the name (instance of a concrete data type) of that concept; the name has to be a lexically meaningful name
  subtype:  akts#has-pretty-name (?,pm#string)
  subtype:  akts#has-variant-name__hasvariantname (?,pm#string)