Daoud, Abazar M. A., Rashed M. A., Kadry N. Sediek, Elamein A. M., and Elsharief A. M. “Barite Concretions in Wadi Halfa Oolitic Ironstone Formation, North Sudan”. Journal of Geography, Environment and Earth Science International 24, no. 5 (July 16, 2020): 51-64. Accessed August 4, 2020. https://journaljgeesi.com/index.php/JGEESI/article/view/30227.