Não informado. (2018). Annual Report. Her Majesty's Stationery Office, Department of the Environment.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Annual Report. London: Her Majesty's Stationery Office, Department of the Environment, 2018.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Annual Report. Her Majesty's Stationery Office, Department of the Environment, 2018.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.