Weakly perturbed boundary-value problems for differential equations in a Banach space. Neliniini Kolyvannya, [S. l.], v. 13, n. 3, p. 291–304, 2010. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/565. Acesso em: 21 jan. 2026.