Cheng, Y, Chon, K.M., Ren, X, Kou, Y, Hwang, M. H. and Chae, K.J., “ The role of Beneficial Microorganisms in an Anoxic-oxic (AO) Process for Treatentof Ammonium-rich Landfill Leachates: Nitrogen Removal and Excess Sludge Reduction”, J. of Environmental Chemical Engineering, Vol. 9, 105188, 2021