%0 Journal Article
%A K. B. Sabitov
%T Maximum modulus principles for some classes of second-order elliptic and hyperbolic systems
%J Differencialʹnye uravneniâ
%D 1991
%P 272-278
%V 27
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1991_27_2_a10/
%G ru
%F DE_1991_27_2_a10