https://w3id.org/framester/conceptnet5/data/en/medgar_evers <https://w3id.org/framester/conceptnet5/schema/InstanceOf> <https://w3id.org/framester/conceptnet5/data/en/person> <https://w3id.org/framester/conceptnet5/data/en/african_american_civil_right_movement.n.1955_68> risorse dalla linked data cloud