MR2075287 Duccio PAPINI and Gabriele VILLARI Duccio PAPINI and Gabriele VILLARI Periodic Solutions of a Certain Generalized Liénard Equation Funkcialaj Ekvacioj. Serio Internacia 47 2004 41--61 http://fe.math.kobe-u.ac.jp/FE/FullPapers/47-1/47_41.pdf http://www.ams.org/mathscinet-getitem?mr=MR2075287 We are concerned with the existence of at least one periodic solution of a generalized nonlinear Liénard equation with a periodic forcing term. The main tool is a continuation theorem by Capietto, Mawhin and Zanolin. A priori bounds for the periodic solutions are obtained either by studying the behavior of the trajectories of a new equivalent system or by determining the nature of singular points at infinity of suitable autonomous systems in the usual phase plane. Generalized Liénard equation, A priori bounds, Periodic solutions. Primary 34B15; Secondary 34C25. 47-41 2004 Periodic Solutions of a Certain Generalized Liénard Equation Duccio PAPINI and Gabriele VILLARI Duccio PAPINI and Gabriele VILLARI
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