Wally, Riyadh Hussein. “A Comparative Study of the Effect of Using RO Water on Zinc and Copper Level and Its Effect on the Level of Hemoglobin in Pregnant Women”. Al-Nahrain Journal of Science 21, no. 1 (March 1, 2018): 46-51. Accessed August 27, 2021. https://anjs.edu.iq/index.php/anjs/article/view/153.