RT Journal Article T1 Existence and Ulam stability for nonlinear implicit differential equations with Riemann-Liouville fractional derivative A1 Benchohra, Mouffak A1 Bouriah, Soufyane A1 Nieto Roig, Juan José K1 Riemann-Liouville fractional derivative K1 Initial value problem K1 Existence K1 Uniqueness K1 Ulam stability K1 Fixed point theorem AB In this paper, we establish the existence and uniqueness of solutions for a class of initial valueproblem for nonlinear implicit fractional differential equations with Riemann-Liouville fractional derivative,also, the stability of this class of problem. The arguments are based upon the Banach contraction principleand Schaefer’s fixed point theorem. An example is included to show the applicability of our results PB De Gruyter SN 0420-1213 YR 2019 FD 2019 LK http://hdl.handle.net/10347/21019 UL http://hdl.handle.net/10347/21019 LA eng NO Benchohra, M., Bouriah, S., & Nieto, J. J. (2019). Existence and Ulam stability for nonlinear implicit differential equations with Riemann-Liouville fractional derivative, Demonstratio Mathematica, 52(1), 437-450. doi: https://doi.org/10.1515/dema-2019-0032 NO The research of J.J. Nieto has been partially supported by the AEI of Spain under Grant MTM2016-75140-P and co-financed by European Community fund FEDER DS Minerva RD 26 abr 2026