%0 Journal Article
%A N. V. Stepanov
%T Geometry of differential equations
%J Itogi Nauki i Tekhniki. Seriya Problemy Geometrii. Trudy Geometricheskogo Seminara
%D 1981
%P 127-164
%V 12
%I mathdoc
%U http://geodesic.mathdoc.fr/item/INTG_1981_12_a4/
%G ru
%F INTG_1981_12_a4