%0 Journal Article %A S. G. Krein %A V. B. Osipov %T Ljapunov functions and Cauchy problems for certain systems of partial differential equations %J Differencialʹnye uravneniâ %D 1970 %P 2053-2061 %V 6 %N 11 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1970_6_11_a13/ %G ru %F DE_1970_6_11_a13