%0 Journal Article %A P. G. Grinevich %A S. P. Novikov %T Discrete $SL_n$-connections and self-adjoint difference operators on two-dimensional manifolds %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 2013 %P 861-887 %V 68 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_2013_68_5_a1/ %G en %F RM_2013_68_5_a1