GUIDORLZZI, H. L. THE FAMILY OF FUNCTIONS $S_{\alpha, k}$ AND THE LIENARD EQUATION. Tamkang Journal of Mathematics, [S. l.], v. 27, n. 1, p. 37–54, 1996. DOI: 10.5556/j.tkjm.27.1996.4368. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4368. Acesso em: 3 may. 2024.