L0 = <http://www.simantics.org/Layer0-1.1>
DIA = <http://www.simantics.org/Diagram-2.2>

DIARegions = <http://www.simantics.org/DistrictDiagramRegions-1.0> : L0.Ontology
    @L0.new
    L0.HasResourceClass "org.simantics.district.region.ontology.DiagramRegionsResource"

DIARegions.Region <T L0.Entity

DIARegions.Region.area <R L0.HasProperty

DIARegions.hasRegion <R L0.IsWeaklyRelatedTo
    L0.InverseOf DIARegions.regionOf <R L0.IsWeaklyRelatedTo
    L0.HasDomain DIA.Diagram