Minceva, M., L. Markovska, and V. Meshko. “Removal of Zn<sup>2+</sup>, Cd<sup>2+</sup> and Pb<sup>2+</sup> From Binary Aqueous Solution by Natural Zeolite and Granulated Activated Carbon”. Macedonian Journal of Chemistry and Chemical Engineering, vol. 26, no. 2, Dec. 2007, pp. 125-34, doi:10.20450/mjcce.2007.267.