(subclass PetroleumLubricant RefinedPetroleumProduct) | Economy.kif 5935-5935 | PetroleumLubricant est une sous-classe de RefinedPetroleumProduct |
(subclass MotorOil PetroleumLubricant) | Economy.kif 5939-5939 | MotorOil est une sous-classe de PetroleumLubricant |