メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.404242606123 44.1671934193739, 142.402167824588 44.1671812111901, 142.402433428236 44.1663373135256, 142.402717902396 44.1663887591079, 142.402828078169 44.1662032914248, 142.404229184877 44.1661943316131, 142.404242606123 44.1671934193739)) ^^http://www.opengis.net/ont/geosparql#wktLiteral