https://w3id.org/framester/conceptnet5/data/en/prime_meridian <https://w3id.org/framester/conceptnet5/schema/IsA> <https://w3id.org/framester/conceptnet5/data/en/earthscape> <https://w3id.org/framester/conceptnet5/data/en/line_of_longitude> risorse dalla linked data cloud