M. H. Gulzar, and A. W. Manzoor. “A Ring-Shaped Region for the Zeros of a Polynomial”. Mathematical Journal of Interdisciplinary Sciences 4, no. 2 (March 30, 2016): 177–182. Accessed April 29, 2024. https://mjis.chitkara.edu.in/index.php/mjis/article/view/89.