FARDIGOLA, L. V. Nonlocal two-point boundary-value problems in a layer with differential operators in the boundary condition. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 47, n. 8, p. 1122–1128, 1995. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5508. Acesso em: 5 dec. 2025.