FARDIGOLA , L. V. Correct problems in a layer with differential operators under the boundary condition. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 8, p. 1083–1090, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8037. Acesso em: 7 apr. 2025.