El-Sayed, A. M. A., R. Gama, and H. R. Ebead. “Solvability of Nonlinear Functional Differential Equations With State-Dependent Derivatives”. Methods of Functional Analysis and Topology 29, no. 1-2 (March 25, 2023): 30–38. Accessed February 4, 2026. https://zen.imath.kiev.ua/index.php/mfat/article/view/845.