United Nations Economic Commission for Europe. (1979). The Gas Situation in the ECE Region Around the Year 1990. ELSEVIER.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रUnited Nations Economic Commission for Europe. The Gas Situation in the ECE Region Around the Year 1990. ELSEVIER, 1979.
एमएलए (8वां संस्करण) प्रशस्ति पत्रUnited Nations Economic Commission for Europe. The Gas Situation in the ECE Region Around the Year 1990. ELSEVIER, 1979.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.