%0 Journal Article %A M. Rakhimov %T The property of being an unconditional basis on a closed interval of systems of eigen- and associated functions of a quadratic pencil of nonselfadjoint differential operators %J Differencialʹnye uravneniâ %D 1986 %P 94-103 %V 22 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1986_22_1_a11/ %G ru %F DE_1986_22_1_a11