Rehman, Rabia, et al. “Kinetic and Isothermal Biosorption Studies of Co(II), Cu(II) and Ni(II) Using Polyalthia Longifolia Leaf Powder”. Asian Journal of Chemistry, vol. 25, no. 15, Sept. 2013, pp. 8285-8, doi:10.14233/ajchem.2013.14713.