%0 Journal Article %A A. V. Savkin %T On the boundedness of trajectories of time-dependent phase systems %J Differencialʹnye uravneniâ %D 1993 %P 1705-1711 %V 29 %N 10 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1993_29_10_a6/ %G ru %F DE_1993_29_10_a6