%0 Journal Article %A V. A. Il'in %A V. V. Tikhomirov %T The basis property of Riesz means of spectral decompositions corresponding to an $n$th-order ordinary nonselfadjoint differential operator %J Differencialʹnye uravneniâ %D 1982 %P 2098-2126 %V 18 %N 12 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1982_18_12_a3/ %G ru %F DE_1982_18_12_a3