%0 Journal Article %A A. M. Minkin %A L. A. Shuster %T Distribution of the spectrum and the convergence of spectral expansions for an operator of Schr\"odinger type %J Differencialʹnye uravneniâ %D 1991 %P 1778-1789 %V 27 %N 10 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1991_27_10_a15/ %G ru %F DE_1991_27_10_a15