Duggal, K. (1996). Elements of environmental engineering (6th ed.). S.Chand & Co.
Čikaški stil citiranjaDuggal, K.N. Elements of Environmental Engineering. 6th ed. New Delhi: S.Chand & Co, 1996.
MLA način citiranjaDuggal, K.N. Elements of Environmental Engineering. 6th ed. S.Chand & Co, 1996.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.