https://w3id.org/framester/conceptnet5/data/en/nitre <https://w3id.org/framester/conceptnet5/schema/EtymologicallyDerivedFrom> <https://w3id.org/framester/conceptnet5/cla/fr.nitre> <https://w3id.org/framester/conceptnet5/cla/la.nitrum> risorse dalla linked data cloud