Não informado. (1970). Environmental quality. Council on Environmental Quality, Executive Office of the President.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Environmental Quality. Washington: Council on Environmental Quality, Executive Office of the President, 1970.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Environmental Quality. Council on Environmental Quality, Executive Office of the President, 1970.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.