1. Banach, S.: Sur les operations dans les ensembles abstraits et leur application aux equations integrales. Fund. Math. 3, 133–181 (1922)
2. Browder, F.E.: Nonexpansive nonlinear operators in a Banach space. Proc. Nat. Acad. Sci. USA 54, 1041–1044 (1965)
3. Kirk, W.A.: A fixed point theorem for mappings which do not increase distance. Am. Math. Mon. 72, 1004–1006 (1965)
4. Cholamjiak, W., Suantai, S., Suparatulatorn, R., Kesornprom, S., Cholamjiak, P.: Viscosity approximation methods for fixed point problems in Hilbert spaces endowed with graphs. J. Appl. Numer. Optim. 1, 25–38 (2019)
5. Khan, S.H., Fukhar-ud-din, H.: Approximating fixed points of $$\rho$$-nonexpansive mappings by RK-iterative process in modular function spaces. J. Nonlinear Var. Anal. 3, 107–114 (2019)