Al-Azzawi, Zeena M, Narges Zamil Abdulzahra, and Iman H Hammood. 2018. “Optical Properties of Tap Water Purity Using He-Ne Laser With Different Power Density”. Al-Nahrain Journal of Science 17 (3): 99-107. https://anjs.edu.iq/index.php/anjs/article/view/410.