%0 Journal Article
%A V. M. Savchin
%T On the structure of variational equations with symmetric operator $d/dt$
%J Differencialʹnye uravneniâ
%D 1993
%P 1765-1771
%V 29
%N 10
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1993_29_10_a11/
%G ru
%F DE_1993_29_10_a11