El Hassan, Osman M, and Abubakr B Alfadil. “Physicochemical Weathering Conditions of the Characteristic White Soil Horizon at Al Firjah Area and it’s Vicinity in North Kordofan State, Central Sudan.”. Journal of The Faculty of Science and Technology, no. 6 (January 13, 2021): 117 - 129. Accessed April 30, 2026. https://journal.oiu.edu.sd/index.php/JFST/article/view/616.