S. A. M. Abbas, “NON-STANDARD DISCRETIZATION METHODS FOR SOME BIOLOGICAL MODELS”, Al-Nahrain J. Sci., vol. 12, no. 1, pp. 126–133, Mar. 2009, Accessed: May 22, 2026. [Online]. Available: https://anjs.edu.iq/index.php/anjs/article/view/1275