Samadi, Ayub, et al. “On a (k;Chi)-Hilfer Fractional System With Coupled Nonlocal Boundary Conditions Including Various Fractional Derivatives and Riemann–Stieltjes Integrals”. Nonlinear Analysis: Modelling and Control, vol. 29, no. 3, May 2024, pp. 426-48, https://doi.org/10.15388/namc.2024.29.34531.