KLEVCHUK, I. I. Homoclinic Points for a Singularly Perturbed System of Differential Equations with Delay. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 54, n. 4, p. 563–567, 2002. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4093. Acesso em: 5 dec. 2025.