AFZALI, M., N. DARIJANI, and A. AMIRI. 2010. “Studies on the Potential of Natural Zeolites and Modified Natural Zeolites Towards the Removal of Heavy Metals from Smoke Cigarette”. Asian Journal of Chemistry 19 (3):1723-27. https://asianpubs.org/index.php/ajchem/article/view/13732.