Macdougall, J. D. (2013). Frozen earth: The once and future story of ice ages. University of California Press.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रMacdougall, J. D. Frozen Earth: The Once and Future Story of Ice Ages. Berkeley: University of California Press, 2013.
एमएलए (9वां संस्करण) प्रशस्ति पत्रMacdougall, J. D. Frozen Earth: The Once and Future Story of Ice Ages. University of California Press, 2013.
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