%0 Journal Article
%A A. H. Hovhannisyan
%T Structure of hyperbolic equations with variable coefficients that
%J Doklady Akademii Nauk
%D 1990
%P 1072-1075
%V 314
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1990_314_5_a11/
%G ru
%F DAN_1990_314_5_a11