APA (7th ed.) Zitazioa
Kramer, S. N. (1959). History begins at Sumer. Doubleday Anchor Books.
Chicago Style (17th ed.) Zitazioa
Kramer, Samuel Noah. History Begins at Sumer. Garden City, New York: Doubleday Anchor Books, 1959.
MLA (9th ed.) Zitazioa
Kramer, Samuel Noah. History Begins at Sumer. Doubleday Anchor Books, 1959.
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