Turk, A., & Wittes, J. T. (1972). Ecology pollution evironment. Saunders Company.
Chicago-čujuhus (17. p.)Turk, Amos, juo Janet T. Wittes. Ecology Pollution Evironment. Saunders Company, 1972.
MLA-čujuhus (9. p.)Turk, Amos, juo Janet T. Wittes. Ecology Pollution Evironment. Saunders Company, 1972.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.