%0 Journal Article %A M. Sh. Birman %A D. R. Yafaev %T The scattering matrix for a perturbation of a periodic Schrödinger operator by decreasing potential %J Algebra i analiz %D 1994 %P 17-39 %V 6 %N 3 %U http://geodesic.mathdoc.fr/item/AA_1994_6_3_a1/ %G ru %F AA_1994_6_3_a1