Levin, H. L. (1996). The Earth through time (5th ed.). Saunders College Pub.
Chicago Style aipamenaLevin, Harold L. The Earth Through Time. 5th ed. Fort Worth: Saunders College Pub, 1996.
MLA aipamenaLevin, Harold L. The Earth Through Time. 5th ed. Saunders College Pub, 1996.
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