%0 Journal Article %A Yu. E. Karpeshina %T Perturbation theory for the Schr\"odinger operator with periodic potential %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1990 %P 88-116 %V 188 %I mathdoc %U http://geodesic.mathdoc.fr/item/TM_1990_188_a4/ %G ru %F TM_1990_188_a4