APAKOV, Yu. P.; DZHURAEV, T. D. On the theory of the third-order equation with multiple characteristics containing the second time derivative. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 62, n. 1, p. 40–51, 2010. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2842. Acesso em: 5 dec. 2025.