5Mujeriego R, Asano T. The role of advanced treatment in wast ewater reclamation and reuse. Wat Sci Tech, 1999,40:1-9
6Water Environment Federation. Upgrading and retrofitting water and wastewater treatment plants,manual of practice No. 28. New York: The McGraw-Hill Company, 2005
7Water Environment Federation. Biological nutrient removal (BNR) operation in wastewater treatment plants,manual of practice No. 30. New York: The McGraw-Hill Company, 2006
8Diagger G T,Buttz J A. Upgrading wastewater treatment plants. London: Technomic, 1998
