MENCINGER, Matej. ON THE CENTRE-FOCUS PROBLEM IN SOME LIÉNARD SYSTEMS. Journal of Energy Technology, [S. l.], v. 10, n. 3, p. 57–69, 2024. DOI: 10.18690/jet.10.3.57-69.2017. Disponível em: https://journals.um.si/index.php/jet/article/view/3756. Acesso em: 6 dec. 2025.