Khaleel, Layla R., et al. “Statistical Indicators for Evaluating the Effect of Heavy Metals on Samaraa Drug Industry Water Exposed to the Sun and Freezing: Http: www.doi.org 10.26538 Tjnpr V6i12.12”. Tropical Journal of Natural Product Research (TJNPR), vol. 6, no. 12, Dec. 2022, pp. 1969-74, https://tjnpr.org/index.php/home/article/view/1401.