APA (7th ed.) Citation

Levin, H. L. (1999). The earth through time (6th ed.). Saunders College Pub.

Chicago Style (17th ed.) Citation

Levin, Harold L. The Earth Through Time. 6th ed. Fort Worth: Saunders College Pub, 1999.

MLA (9th ed.) Citation

Levin, Harold L. The Earth Through Time. 6th ed. Saunders College Pub, 1999.