Não informado. (1956). Bulletin. International Union for Conservation of Nature and Natural Resources.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Bulletin. Brussels: International Union for Conservation of Nature and Natural Resources, 1956.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Bulletin. International Union for Conservation of Nature and Natural Resources, 1956.
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