%0 Journal Article
%A V. A. Efremovich
%T Qualitative properties of figures
%J Doklady Akademii Nauk
%D 1988
%P 1048-1050
%V 302
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1988_302_5_a4/
%G ru
%F DAN_1988_302_5_a4