ASTAF’EVA, M. M.; STEPANENKO, N. V. Sets of linear expansions of dynamical systems on a torus for a fixed Lyapunov function. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 59, n. 12, p. 1707–1713, 2007. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3425. Acesso em: 6 dec. 2025.