Amatya, Iswar Man, Bhagwan Ratna Kansakar, Vinod Tare, and Liv Fiksdal. “Role of PH on Biological Nitrification Process”. Journal of the Institute of Engineering 8, no. 1-2 (July 20, 2011): 119–125. Accessed April 26, 2024. https://www.nepjol.info/index.php/JIE/article/view/5102.