Turk, A., & Wittes, J. T. (1972). Ecology pollution evironment. Saunders Company.
Cita Chicago (17th ed.)Turk, Amos, i Janet T. Wittes. Ecology Pollution Evironment. Saunders Company, 1972.
Cita MLA (9th ed.)Turk, Amos, i Janet T. Wittes. Ecology Pollution Evironment. Saunders Company, 1972.
Atenció: Aquestes cites poden no estar 100% correctes.