DRAGUNOV, D. V.; MAKAROV, V. L.; SEMBER, D. A. FD-method for solving the nonlinear Klein - Gordon equation. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 64, n. 10, p. 1394–1415, 2012. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2667. Acesso em: 5 dec. 2025.