Relation pm#related_to__relatedto (?,?)  the '&' link in WebKB-2 (currently used for representing a sumo#related_internal_concept relation)
  subtype:  related_internal_concept  the two arguments are related concepts within the SUMO, i.e. there is a significant similarity of meaning between them; to indicate a meaning relation between a SUMO concept and a concept from another source, use sumo#related_external_concept
  related_to:  related_external_concept (pm)
  supertype:  similar (?,?)  DO NOT USE SUCH A RELATION TYPE DIRECTLY
     supertype:  equivalence_relation__equivalencerelation (?,?)  this category only serves structuration purposes: it is instance of pm#equivalence_relation_type which is not instance of pm#class_of_inheritable_relation_type
        supertype:  reflexive_relation__reflexiverelation (?,?)  this category only serves structuration purposes: it is instance of pm#reflexive_relation_type which is not instance of pm#class_of_inheritable_relation_type
           supertype:  binary_relation_with_particular_mathematical_property (?,?)
              supertype:  relation_with_particular_mathematical_property (*)
                 supertype:  relation_with_particular_property (*)  this rather fuzzy type permits to group categorization schemes less common than those covered by the previous sibling categories
                    >part of:  relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type
        supertype:  symmetric_relation__symmetricrelation (?,?)  this category only serves structuration purposes: it is instance of pm#symmetric_relation_type which is not instance of pm#class_of_inheritable_relation_type
           supertype:  binary_relation_with_particular_mathematical_property (?,?)
        supertype:  transitive_relation (?,?)  this category only serves structuration purposes: it is instance of pm#transitive_relation_type which is not instance of pm#class_of_inheritable_relation_type
           supertype:  binary_relation_with_particular_mathematical_property (?,?)