メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.7937500 42.3291667, 139.8000000 42.3291667, 139.8000000 42.3333333, 139.7937500 42.3333333, 139.7937500 42.3291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral