%0 Journal Article %A V. L. Popov %T Closed orbits of Borel subgroups %J Sbornik. Mathematics %D 1989 %P 375-392 %V 63 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_1989_63_2_a7/ %G en %F SM_1989_63_2_a7