Makundi, Ismael N, Mungubariki M Nyaki, and Najat K Mohammed. 2021. “Assessment of Radioactivity Levels in Coal and Coal Ash in Kiwira Coal Mine Using Gamma-Ray Spectrometry”. Tanzania Journal of Science 44 (3):1-11. https://tjs.udsm.ac.tz/index.php/tjs/article/view/283.