%0 Journal Article %A Chen, Chao-Nien %A Tzeng, Shyuh-yaur %T Existence and multiplicity results for homoclinic orbits of Hamiltonian systems %J Electronic Journal of Differential Equations %D 1997 %V 1997 %I mathdoc %U http://geodesic.mathdoc.fr/item/EJDE_1997__1997__a27/ %G en %F EJDE_1997__1997__a27