Idrees, Shenwar A., Lawand L. Mustafa, and Sabah S. Saleem. “Improvement Viscosity Index of Lubricating Engine Oil Using Low Molecular Weight Compounds”. Science Journal of University of Zakho 7, no. 1 (March 30, 2019): 14–17. Accessed April 20, 2024. https://sjuoz.uoz.edu.krd/index.php/sjuoz/article/view/572.