KATRIEL, G. Uniqueness of periodic solutions for asymptotically linear Duffing equations with strong forcing. Topological Methods in Nonlinear Analysis, [S. l.], v. 12, n. 2, p. 263–274, 1998. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1998.041. Acesso em: 22 jul. 2024.