メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.422146941713 43.7681825282851, 142.421534796246 43.7682106861314, 142.420950067761 43.7682404180478, 142.420866695276 43.7674566248898, 142.421462702334 43.7674207232055, 142.422047984252 43.7673926046836, 142.422146941713 43.7681825282851)) ^^http://www.opengis.net/ont/geosparql#wktLiteral