%0 Journal Article
%A A. I. Perov
%A V. L. Khatskevich
%T Regularity classes of bilinear forms, and nonlinear elliptic boundary value problems
%J Differencialʹnye uravneniâ
%D 1988
%P 464-476
%V 24
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1988_24_3_a12/
%G ru
%F DE_1988_24_3_a12