%0 Journal Article %A A. I. Komech %T Elliptic boundary value problems on manifolds with a~piecewise smooth boundary %J Sbornik. Mathematics %D 1973 %P 91-135 %V 21 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_1973_21_1_a4/ %G en %F SM_1973_21_1_a4