%0 Journal Article %A V. N. Shchennikov %T Investigation of convergence in a nonautonomous differential system by means of Lyapunov vector-functions %J Differencialʹnye uravneniâ %D 1983 %P 1902-1907 %V 19 %N 11 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1983_19_11_a10/ %G ru %F DE_1983_19_11_a10