Theory of Fractional Differential Equations in a Banach Space. European Journal of Pure and Applied Mathematics, Maryland, USA, v. 1, n. 1, p. 38–45, 2007. DOI: 10.29020/nybg.ejpam.v1i1.84. Disponível em: https://www.ejpam.com/index.php/ejpam/article/view/84. Acesso em: 7 apr. 2025.