メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1937500 38.6708334, 141.2000000 38.6708334, 141.2000000 38.6750000, 141.1937500 38.6750000, 141.1937500 38.6708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral