Hamoud, Ahmed A., and Nedal M. Mohammed. “Hyers-Ulam and Hyers-Ulam-Rassias Stability of Nonlinear Volterra-Fredholm Integral Equations”. Discontinuity, Nonlinearity, and Complexity, vol. 11, no. 3, Aug. 2026, pp. 515-21, https://doi.org/10.5890/DNC.2022.09.012.