Riaz, Muhammad, et al. “Kinetic and Equilibrium Modeling of Lead(II) Sorption onto Chemically Pretreated Gossypium Hirsutum (Cotton) Leaves Waste Biomass”. Asian Journal of Chemistry, vol. 25, no. 2, Sept. 2012, pp. 1111-6, doi:10.14233/ajchem.2013.13610.