Não informado. (1980). Singapore journal of tropical geography. National University od Singapore, Department of Geography.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Singapore Journal of Tropical Geography. Singapore: National University od Singapore, Department of Geography, 1980.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Singapore Journal of Tropical Geography. National University od Singapore, Department of Geography, 1980.
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