MALYTS’KA, H. P. The third mixed problem for the Sonin equation in a half space. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 45, n. 8, p. 1109–1114, 1993. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5907. Acesso em: 5 dec. 2025.