ROZHANKOVSKAYA, M. I.; SYAVAVKO, M. S. Transformation of formal expansions of solutions of linear differential equations in a parameter into continued RITZ-fractions. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 50, n. 5, p. 679–686, 1998. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4906. Acesso em: 7 apr. 2025.