%0 Journal Article
%T Existence of periodic solutions for non-autonomous second-order Hamiltonian systems
%A Yue Wu
%A Tianqing An
%J Electronic Journal of Differential Equations
%D 2013
%I Texas State University
%X The purpose of this paper is to study the existence of periodic solutions for a class of non-autonomous second order Hamiltonian systems. New results are obtained by using the least action principle and the minimax methods, without the so-called Ahmad-Lazer-Paul type condition.
%K Periodic solution
%K Hamiltonian systems
%K critical point
%K variational method
%U http://ejde.math.txstate.edu/Volumes/2013/77/abstr.html