APA (7th ed.) Zitazioa
Macdougall, J. D. Frozen Earth: The Once and Future Story of Ice Ages. University of California.
Chicago Style (17th ed.) Zitazioa
Macdougall, J. Doug. Frozen Earth: The Once and Future Story of Ice Ages. Berkeley, EUA: University of California.
MLA (9th ed.) Zitazioa
Macdougall, J. Doug. Frozen Earth: The Once and Future Story of Ice Ages. University of California.
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