Two nontrivial homoclinic orbits for a class of nonperiodic  perturbed Hamiltonian systems. Nonlinear Studies, [S. l.], v. 32, n. 4, p. 1237–1248, 2025. Disponível em: https://www.nonlinearstudies.com/index.php/nonlinear/article/view/3899. Acesso em: 14 jan. 2026.