%0 Journal Article %A Jürgen Pöschel %T Quasi-periodic solutions for a nonlinear wave equation. %J Commentarii mathematici Helvetici %D 1996 %P 269 %V 71 %N 2 %I mathdoc %U https://geodesic-test.mathdoc.fr/item/CMH_1996__71_2_140400/ %G un %F CMH_1996__71_2_140400