%0 Journal Article
%A A. A. Davydov
%T Singularities of fields of limiting directios of two-dimensional control systems
%J Sbornik. Mathematics
%D 1989
%P 471-493
%V 64
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/SM_1989_64_2_a12/
%G en
%F SM_1989_64_2_a12