%0 Journal Article
%A N. I. Kovantsov
%T A ruled surface geometry analogue to a triorthogonal system of surfaces
%J Doklady Akademii Nauk
%D 1957
%P 497-500
%V 113
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1957_113_3_a3/
%G ru
%F DAN_1957_113_3_a3