ALDASHEV, S. A. Nonuniqueness of the solution of the gellerstedt space problem for one class of many-dimensional hyperbolic-elliptic equations. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 62, n. 2, p. 265–269, 2010. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2862. Acesso em: 5 dec. 2025.