On Solution of Regular Singular Ordinary Boundary Value Problem. Ibn AL-Haitham Journal For Pure and Applied Sciences, [S. l.], v. 26, n. 2, p. 249–256, 2017. Disponível em: https://jih.uobaghdad.edu.iq/index.php/j/article/view/473.. Acesso em: 3 may. 2024.