8.1 IfcActorResource
8.2 IfcGeometricConstraintResource
8.3 IfcGeometricModelResource
8.4 IfcGeometryResource
8.5 IfcMaterialResource
8.6 IfcMeasureResource
8.7 IfcProfileResource
8.8 IfcPropertyResource
8.9 IfcQuantityResource
8.10 IfcRepresentationResource
8.11 IfcTopologyResource
8.12 IfcUtilityResource