%0 Journal Article
%A Chengfu Che
%A Xiaoping Xue
%T Periodic solutions for second order Hamiltonian systems
 on an arbitrary energy surface
%J Annales Polonici Mathematici
%D 2012
%P 1-12
%V 105
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.4064/ap105-1-1/
%R 10.4064/ap105-1-1
%G en
%F 10_4064_ap105_1_1