%0 Journal Article
%A S. E. Karapetyan
%T Second order Lie surface for ruled surfaces of congruence
%J Doklady Akademii Nauk
%D 1957
%P 177-179
%V 117
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1957_117_2_a3/
%G ru
%F DAN_1957_117_2_a3