Ghaffar, Abdul, and Muhammad Aslam. “Optimization of Physiochemical Conditions for Removal of Copper (II) Ions from Industrial Effluents Using Various Sorbents”. Asian Journal of Chemistry, vol. 18, no. 3, Mar. 2010, pp. 1853-61, https://asianpubs.org/index.php/ajchem/article/view/20888.