N. Derdar, M. . Alshammari, S. . Alshammari, and M. S. Abdo, “Existence and Stability of Nonlinear Langevin FDEs with Mixed <i>ψ</i>-Hilfer and <i>ψ</i>-Caputo Derivatives Under Nonlocal Boundary Conditions”, Contemp. Math., vol. 7, no. 1, pp. 742–773, Jan. 2026.