Petroleum Institute of the Philippines, Inc. (1971). The oil industry in crisis. s.n.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रPetroleum Institute of the Philippines, Inc. The Oil Industry in Crisis. [Manila: s.n, 1971.
एमएलए (9वां संस्करण) प्रशस्ति पत्रPetroleum Institute of the Philippines, Inc. The Oil Industry in Crisis. s.n, 1971.
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