Não informado. (1976). Water quality bulletin. World Health Organization, Collaborating Centre on Surface and Ground Water.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Water Quality Bulletin. Ontario, Canada: World Health Organization, Collaborating Centre on Surface and Ground Water, 1976.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Water Quality Bulletin. World Health Organization, Collaborating Centre on Surface and Ground Water, 1976.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.