メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.9125000 42.4291667, 139.9187500 42.4291667, 139.9187500 42.4333333, 139.9125000 42.4333333, 139.9125000 42.4291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral