%0 Journal Article
%A A. N. Varchenko
%T On~normal forms of nonsmoothness of solutions of hyperbolic equations
%J Izvestiya. Mathematics 
%D 1988
%P 615-628
%V 30
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM2_1988_30_3_a8/
%G en
%F IM2_1988_30_3_a8