Existence and Multiplicity of Positive Solutions for a Singular Nonlinear High Order Fractional Differential Problem with Multi-Point Boundary Conditions. Journal of Nonlinear Modeling and Analysis, [S. l.], v. 3, n. 4, p. 603–616, 2024. DOI: 10.12150/jnma.2021.603. Disponível em: https://global-sci.com/index.php/jnma/article/view/13619. Acesso em: 5 dec. 2025.