Não informado. (1960). Geomorphological abstracts. Department of Geography, School of Economics and Political Science.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Geomorphological Abstracts. London: Department of Geography, School of Economics and Political Science, 1960.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Geomorphological Abstracts. Department of Geography, School of Economics and Political Science, 1960.
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