Almuslet, N., and E. Mirgani. “Identification of Heavy Metals in Some Water Sources in Khartoum State Using Laser Induced Breakdown Spectroscopy”. International Journal of Sciences: Basic and Applied Research (IJSBAR), vol. 35, no. 2, Aug. 2017, pp. 206-11, https://www.gssrr.org/index.php/JournalOfBasicAndApplied/article/view/7796.