%0 Journal Article
%A Jan Persson
%T Non-Uniqueness and Uniqueness in the Cauchy Problem at Simple Characteristic Points.
%J Mathematische Annalen
%D 1973
%P 231-238
%V 203
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MAN_1973__203_162444/
%F MAN_1973__203_162444