KOCHERGA, O. I. Asymptotic solution of the cauchy problem for a singularly perturbed linear system. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 51, n. 8, p. 1126–1128, 1999. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4705. Acesso em: 5 dec. 2025.