LEVIN, H. L. (1983). The earth through time.-- ed.2. Saunders College.
Chicago-čujuhus (17. p.)LEVIN, Harold L. The Earth Through Time.-- Ed.2. New York: Saunders College, 1983.
MLA-čujuhus (9. p.)LEVIN, Harold L. The Earth Through Time.-- Ed.2. Saunders College, 1983.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.