A boundary-value problem for a loaded mixed-type equation with a characteristic line of type change. Neliniini Kolyvannya, [S. l.], v. 24, n. 3, p. 306–317, 2021. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/1032. Acesso em: 6 dec. 2025.