%0 Journal Article
%A V. I. Matsaev
%T The existence of transformation operators for differential equations of higher order
%J Doklady Akademii Nauk
%D 1960
%P 499-502
%V 130
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1960_130_3_a3/
%G ru
%F DAN_1960_130_3_a3