%0 Journal Article
%A V. Ya. Ivrii
%A V. M. Petkov
%T Necessary conditions for the Cauchy problem for non-strictly hyperbolic equations to be well-posed
%J Trudy Matematicheskogo Instituta imeni V.A. Steklova
%D 1974
%P 1-70
%V 29
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/RM_1974_29_5_a0/
%G en
%F RM_1974_29_5_a0