%0 Journal Article
%A R. N. Shcherbakov
%T Projective invariant marks of a ruled surface belonging to a given congruence
%J Doklady Akademii Nauk
%D 1957
%P 390-393
%V 112
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1957_112_3_a5/
%G ru
%F DAN_1957_112_3_a5