Abdullah , Dawoud .S, Ava Rafeeq, and Raad N. Butris. “Existence Uniqueness and Stability for Certain Operators of Nonlinear System of Differential Equations”. Bulletin of Social Informatics Theory and Application 7, no. 2 (December 5, 2023): 193–204. Accessed September 2, 2025. https://pubs.ascee.org/index.php/businta/article/view/656.