- Plant Ontology CC-BY-4.0
Plant Ontology project; original artifact license CC-BY-4.0 (http://creativecommons.org/licenses/by/4.0/); https://obofoundry.org/ontology/po.html
http://purl.obolibrary.org/obo/PO_0004540 ; https://purl.obolibrary.org/obo/po.owl ; snapshot SHA-256 a066a2091b96dc6c960683a67936ccda4926afd96e4edb22df9e30feec16e9e0 ; exact artifact license http://creativecommons.org/licenses/by/4.0/ ; retrieved 2026-11-07