%0 Journal Article
%A R. M. Geidel'man
%T The theory of a hypersurface in four-dimensional non-Euclidean spaces
%J Doklady Akademii Nauk
%D 1961
%P 1040-1043
%V 139
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1961_139_5_a2/
%G ru
%F DAN_1961_139_5_a2