APA
Water & Environment Federation, . (2006). Biological Nutrient Removal (BNR) Operation in Waster water Treatment Plants. New York: McGraw-Hill.
Chicago
Water & Environment Federation, . 2006. Biological Nutrient Removal (BNR) Operation in Waster water Treatment Plants. New York: McGraw-Hill.
Harvard
Water & Environment Federation, . (2006). Biological Nutrient Removal (BNR) Operation in Waster water Treatment Plants. New York: McGraw-Hill.
MLA
Water & Environment Federation, . Biological Nutrient Removal (BNR) Operation in Waster water Treatment Plants. New York: McGraw-Hill. 2006.