India. Dept. of Petroleum. (1981). Annual report. Govt. of India, Ministry of Petroleum, Chemicals, and Fertilizers, Dept. of Petroleum.
Chicago-viite (17. p.)India. Dept. of Petroleum. Annual Report. New Delhi: Govt. of India, Ministry of Petroleum, Chemicals, and Fertilizers, Dept. of Petroleum, 1981.
MLA-viite (8. p.)India. Dept. of Petroleum. Annual Report. Govt. of India, Ministry of Petroleum, Chemicals, and Fertilizers, Dept. of Petroleum, 1981.
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