KOLOS, I.; KOLOS, M. Approximate solution of a generalized boundary value problem for hyperbolic-type equations with degeneracy. Numerical Methods and Programming (Vychislitel’nye Metody i Programmirovanie), [S. l.], v. 6, n. 6, p. 283–289, 2005. Disponível em: https://en.num-meth.ru/index.php/journal/article/view/171. Acesso em: 28 apr. 2024.