"Hazards Arising from Working in Confined Spaces Case Study: Khartoum North Industrial Area, Sudan". University of Khartoum Engineering Journal 5, no. 1 (نوفمبر 1, 2022). تاريخ الوصول يوليو 8, 2026. https://onlinejournals.uofk.edu/kuej/article/view/1023.