%0 Journal Article %A E. I. Glazman %T Extensions of differential-difference operators with periodic %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1978 %P 229-230 %V 33 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1978_33_2_a9/ %G en %F RM_1978_33_2_a9