UML allows the cardinality of a property to be left unspecified. The concept modeling profile interprets unspecified cardinalities as being zero to many (“0..*”).

A class with property whose multiplicity is unspecified.
Ontology(<http://nomagic.com/ontology/example-case/case-21>
      Declaration(
             Class(:SoccerPlayer)
      )
      Declaration(
             Class(:SoccerTeam)
      )
      Declaration(ObjectProperty(:consistsOf))
      AnnotationAssertion(rdfs:label:SoccerPlayer "Soccer Player"@en)
      AnnotationAssertion(rdfs:label :SoccerTeam "Soccer Team"@en)
      AnnotationAssertion(rdfs:label :consistsOf "consists of"@en)
      ObjectPropertyDomain(:consistsOf :SoccerTeam)
      ObjectPropertyRange(:consistsOf :SoccerPlayer)
)

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