メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.392892704256 44.1740946449824, 142.392163233719 44.1739688378424, 142.392433911265 44.1729282030224, 142.393217360791 44.1730451153986, 142.392892704256 44.1740946449824)) ^^http://www.opengis.net/ont/geosparql#wktLiteral