Kitalika, A., R. Machunda, H. Komakech, and K. N. . Njau. “Assessment of Water Quality Variation in Rivers through Comparative Index Technique and Its Reliability for Decision Making”. Tanzania Journal of Science, vol. 44, no. 3, Apr. 2021, pp. 163-91, https://tjs.udsm.ac.tz/index.php/tjs/article/view/570.