Levorsen, A. I. (1967). Geology of petroleum (2nd ed.). Feffer and Simons.
Chicago Style aipamenaLevorsen, A. I. Geology of Petroleum. 2nd ed. Bombay: Feffer and Simons, 1967.
MLA aipamenaLevorsen, A. I. Geology of Petroleum. 2nd ed. Feffer and Simons, 1967.
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