Mohammadi Moreveg, Parvin, and Hamid Golchoubian. “Hydrometallurgical Process for Recovery of Cadmium from the Plant Sewage Sludge”. Asian Journal of Chemistry, vol. 18, no. 3, Mar. 2010, pp. 1690-0, https://asianpubs.org/index.php/ajchem/article/view/20857.