SOSNITSKII, S. P. On one atypical scheme of application of the second Lyapunov method. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 61, n. 11, p. 1557–1563, 2009. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3121. Acesso em: 11 apr. 2025.