%0 Journal Article %A A. K. Tolpygo %T Nonabelian two-dimensional cohomology %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1972 %V 27 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1972_27_5_a23/ %G ru %F RM_1972_27_5_a23