Não informado. World environment report. Center for International Environment Information.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. World Environment Report. New York: Center for International Environment Information.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. World Environment Report. Center for International Environment Information.
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