(subclass Sanitation Removing) | Geography.kif 2915-2915 | Sanitation is a subclass of removing |
(subclass SewageDisposal Sanitation) | Geography.kif 2920-2920 | Sewage disposal is a subclass of sanitation |
(subclass SolidWasteDisposal Sanitation) | Geography.kif 2921-2921 | Solid waste disposal is a subclass of sanitation |