%0 Journal Article %A Yves Elskens %T Finite-N dynamics admit no travelling-waves solutions for the Hamiltonian XY model and single-wave collisionless plasma model %J ESAIM. Proceedings %D 2001 %P 221-215 %V 10 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.1051/proc:2001008/ %R 10.1051/proc:2001008 %G en %F EP_2001_10_a12