OPINION — AG — ** AD VALOREM TAXATION — OIL AND GAS — PRODUCTION ** LAND ACTUALLY NECESSARY AND BEING USED IN THE PRODUCTION OF PETROLEUM AND NATURAL GAS IS SUBJECT TO AD VALOREM TAXATION NOTWITHSTANDING THE " IN LIEU OF " PROVISIONS OF 68 O.S. 1001 [68-1001](H) (EQUIPMENT, PROPERTY, GROSS PRODUCTION, CASINGHEAD GAS, DOCTRINE OF ' EJUSDEM GENERIS ', EQUIPMENT ACTUALLY USED IN THE PRODUCTION) CITE: 68 O.S. 1001 [68-1001](H), 68 O.S. 1001 [68-1001] [68-1001](B), 68 O.S. 1001 [68-1001](H) (JOHN D. ROTHMAN)