Asymptotics of solutions of boundary-value problems for linear singularly perturbed systems of differential equations in the case of a multiple spectrum of the boundary matrix. Neliniini Kolyvannya, [S. l.], v. 21, n. 4, p. 444–456, 2018. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/921. Acesso em: 21 jan. 2026.