%0 Journal Article %T Seminar on qualitative theory of differential equations at Moscow State University %J Differencialʹnye uravneniâ %D 2000 %P 852-860 %V 36 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_2000_36_6_a22/ %G ru %F DE_2000_36_6_a22