D. Kuchar and  T. Fukuta and  M. Kubota and  H. Matsuda,  Recovery of Cu, Zn, Ni and Cr from Plating Sludge by Combined Sulfidation and Oxidation Treatment.   journal   = {International Journal of Chemical and Molecular Engineering}, [online]. World Academy of Science, Engineering and Technology.
    August 2008, vol. 20(8). 153 - 157
    [viewed 23 April 2021]. Available from: https://publications.waset.org/pdf/6801.