LAVRENYUK, S. P.; PUKACH, P. Ya. Mixed problem for a nonlinear hyperbolic equation in a domain unbounded with respect to space variables. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 59, n. 11, p. 1523–1531, 2007. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3408. Acesso em: 6 dec. 2025.