%0 Journal Article %A S. A. Nazarov %T Singularities of the gradient of the solution of the Neumann problem at the vertex of a cone %J Matematičeskie zametki %D 1987 %P 79-93 %V 42 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_1987_42_1_a8/ %G ru %F MZM_1987_42_1_a8