Theng, M. L., L. S. Tan, and W. C. Siaw. “Adsorption of Methylene Blue and Congo Red Dye from Water onto Cassava Leaf Powder”. Progress in Energy and Environment, vol. 12, Apr. 2020, pp. 11-21, https://www.akademiabaru.com/submit/index.php/progee/article/view/1061.