Não informado. (2017). Petroleum Engineer. Petroleum Engineer Publications.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Petroleum Engineer. Dallas, Tex: Petroleum Engineer Publications, 2017.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Petroleum Engineer. Petroleum Engineer Publications, 2017.
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