Karrar, Osama SeedAhmed, et al. “Microbial Analysis and Safety of Drinking Water in Northern and Southern Darfur”. International Journal of Sciences: Basic and Applied Research (IJSBAR), vol. 24, no. 6, Nov. 2015, pp. 373-84, https://www.gssrr.org/JournalOfBasicAndApplied/article/view/4962.