Existence of solutions for boundary valued problems of fractional integro-differential equations with integral boundary conditions on Banach spaces. Nonlinear Studies, [S. l.], v. 26, n. 3, 2019. Disponível em: https://www.nonlinearstudies.com/index.php/nonlinear/article/view/1732. Acesso em: 28 feb. 2026.