LITOVCHENKO, V. A. Hyperbolic systems in Gelfand and Shilov spaces. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 71, n. 10, p. 1360–1373, 2019. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1520. Acesso em: 5 dec. 2025.