%0 Journal Article %A È. I. Grudo %T Structure of the solutions of an autonomous Pfaffian system with two pure imaginary roots of the characteristic equation %J Differencialʹnye uravneniâ %D 1988 %P 760-770 %V 24 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1988_24_5_a2/ %G ru %F DE_1988_24_5_a2