APA (7e ed.) Bronvermelding

Levin, H. L. (1983). The earth through time (2nd ed.). Saunders College Pub..

Chicago (17e ed.) Bronvermelding

Levin, Harold L. The Earth Through Time. 2nd ed. Philadelphia: Saunders College Pub., 1983.

MLA (8e ed.) Bronvermelding

Levin, Harold L. The Earth Through Time. 2nd ed. Saunders College Pub., 1983.