Lakhani, A., S. Zehra, and Q. Laraib. “Slow Sand Filtration: A Cost-Effective and Straightforward Approach to Water Purification”. PAKISTAN JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY, vol. 56, no. 4, June 2024, pp. 180-91, http://pjbmb.com/index.php/pjbmb/article/view/113.