%0 Journal Article
%A S. V. Buyalo
%T Euclidean planes in open three-dimensional manifolds of nonpositive curvature
%J Algebra i analiz
%D 1991
%P 102-117
%V 3
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/AA_1991_3_1_a3/
%G ru
%F AA_1991_3_1_a3