PROTSAKH, N. P. Properties of solutions of a mixed problem for a nonlinear ultraparabolic equation. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 61, n. 6, p. 795–809, 2009. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3059. Acesso em: 27 apr. 2025.