Dyfyniad APA

Levorsen, A. I. (1972). Geology of petroleum. Vakils, Feffer and Simons.

Dyfyniad Arddull Chicago

Levorsen, A I. Geology of Petroleum. Bombay: Vakils, Feffer and Simons, 1972.

Dyfyniad MLA

Levorsen, A I. Geology of Petroleum. Vakils, Feffer and Simons, 1972.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.