%0 Journal Article %A È. I. Grudo %T The stability of characteristic vectors of the solutions of linear homogeneous Pfaffian systems %J Differencialʹnye uravneniâ %D 1978 %P 2136-2146 %V 14 %N 12 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1978_14_12_a3/ %G ru %F DE_1978_14_12_a3