N. Hasseb,D , and A. Al-Jumaily,H . "Assessment of Levels of Elements Concentrations (Pb, As, Cr) in Groundwater and its Environmental Impacts in the Yaychi Region, Kirkuk / Northern Iraq", Kirkuk Journal of Science, 15, 1, 2020, 34-52. doi: 10.32894/kujss.2020.15.1.3