M. Azzam, Ahmed, and Ahmed Tawfik. “Removal of Heavy Metals Using Bacterial Bio-Flocculants of Bacillus Sp. And Pseudomonas Sp”. Journal of Environmental Engineering and Landscape Management, vol. 23, no. 4, Nov. 2015, pp. 288-94, https://doi.org/10.3846/16486897.2015.1068781.