%0 Journal Article %A Vejvoda, Otto %A Krejčí, Pavel %T A note to a bifurcation result of H. Kielhöfer for the wave equation %J Mathematica Bohemica %D 1991 %P 245-247 %V 116 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.21136/MB.1991.126179/ %R 10.21136/MB.1991.126179 %G en %F 10_21136_MB_1991_126179