%0 Journal Article %A Klaus Thews %T T-Periodic Solutions of Time Dependent Hamiltonian Systems with a Potential Vanishing at Infinity. %J Manuscripta mathematica %D 1980 %P 327-338 %V 33 %I mathdoc %U http://geodesic.mathdoc.fr/item/MM2_1980__33_154752/ %F MM2_1980__33_154752