%0 Journal Article %A J.M. Coron %T Periodic Solutions of a Nonlinear Wave Equation Without Assumption of Monotonicity. %J Mathematische Annalen %D 1983 %P 273-286 %V 262 %I mathdoc %U http://geodesic.mathdoc.fr/item/MAN_1983__262_163706/ %F MAN_1983__262_163706