メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.1750000 37.8416667, 139.1812500 37.8416667, 139.1812500 37.8458334, 139.1750000 37.8458334, 139.1750000 37.8416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral