メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5500000 39.1416667, 141.5562500 39.1416667, 141.5562500 39.1458334, 141.5500000 39.1458334, 141.5500000 39.1416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral