@prefix owl: . @prefix rdfs: . @prefix skos: . @prefix unit: . unit:SI_code a owl:AnnotationProperty ; rdfs:label "SI code" . unit:UCUM_code a owl:AnnotationProperty ; rdfs:label "UCUM code" . unit:ng-1 a owl:NamedIndividual ; rdfs:label "reciprocal nanogram"@en ; skos:definition "A unit which is equal to the reciprocal of 10⁻⁹ gram."@en ; unit:SI_code "ng-1" ; unit:UCUM_code "/ng", "ng-1" .