%0 Journal Article
%A Hidekazu Ito
%T Integrability of Hamiltonian systems and Birkhoff normal forms in the simple resonance case.
%J Mathematische Annalen
%D 1992
%P 411-444
%V 292
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MAN_1992__292_2_164922/
%F MAN_1992__292_2_164922