A. M. A. El-Sayed, R. Gama, and H. R. Ebead, “Solvability of nonlinear functional differential equations with state-dependent derivatives”, MFAT, vol. 29, no. 1-2, pp. 30–38, Mar. 2023, doi: https://doi.org/10.31392/MFAT-npu26_1–2.2023.03.