%0 Journal Article %A M. O. Otelbaev %T A criterion for the coincidence of extensions, corresponding to Dirichlet's and Neumann's problems, of an elliptic operator %J Matematičeskie zametki %D 1981 %P 867-875 %V 29 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_1981_29_6_a7/ %G ru %F MZM_1981_29_6_a7