No TPTP formula. May not be expressible in strict first order. | Mid-level-ontology.kif 1677-1677 | Petroleum product is a subclass of oil |
No TPTP formula. May not be expressible in strict first order. | Mid-level-ontology.kif 1688-1688 | Fossil fuel is a subclass of petroleum product |
No TPTP formula. May not be expressible in strict first order. | Economy.kif 5684-5684 | Petroleum is a subclass of petroleum product |
No TPTP formula. May not be expressible in strict first order. | Economy.kif 5929-5929 | Refined petroleum product is a subclass of petroleum product |