Noaman, Ysri, and El-Sayed A.M.A. “On a Nonlocal Boundary Value Problem of a Coupled System of Volterra Functional Integro-Dierential Equations”. JOURNAL OF ADVANCES IN MATHEMATICS 11, no. 3 (September 1, 2015): 5041–5049. Accessed May 4, 2025. https://rajpub.com/index.php/jam/article/view/3553.