%0 Journal Article
%A L. M. Lerman
%A Ya. L. Umanskii
%T Isoenergetic classification of integrable Hamiltonian systems in a neighborhood of a simple elliptic point
%J Matematičeskie zametki
%D 1994
%P 88-97
%V 55
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MZM_1994_55_5_a8/
%G ru
%F MZM_1994_55_5_a8