FELLER, M. N. Boundary-value problems for a nonlinear hyperbolic equation with divergent part and Levy Laplacian. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 64, n. 2, p. 237–244, 2012. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2570. Acesso em: 27 apr. 2025.