%0 Journal Article
%A A. I. Koshelev
%T On the differentiability of solutions of elliptical differential equations
%J Doklady Akademii Nauk
%D 1957
%P 806-809
%V 112
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1957_112_5_a5/
%G ru
%F DAN_1957_112_5_a5