Boundary value problems for the system of operator-differential equations in the Banach and Hilbert spaces. Neliniini Kolyvannya, [S. l.], v. 24, n. 3, p. 329–335, 2021. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/1034. Acesso em: 8 dec. 2025.