CABALLERO, Josefa, HARJANI, Jackie, LÓPEZ, Belén and SADARANGANI, Kishin. Existence of positive solutions in the space of Hölder functions for a class of nonlinear fractional differential equations with integral boundary conditions. Topological Methods in Nonlinear Analysis. Online. 3 March 2024. Vol. 63, no. 1, pp. 185 - 196. [Accessed 24 July 2024]. DOI 10.12775/TMNA.2023.038.