KLYMENKO, Ya. V.; MAKAROV, V. L. Application of the FD-method to the solution of the Sturm-Liouville problem with coefficients of special form. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 59, n. 8, p. 1140–1147, 2007. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3377. Acesso em: 6 dec. 2025.