%0 Journal Article
%A Lawrence. Corwin
%A B. Helffer
%T Smoothness and analycity for solutions of first order systems of partial differential equations on nilpotent Lie groups.
%J Inventiones mathematicae
%D 1985
%P 205-216
%V 81
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM_1985__81_143253/
%F IM_1985__81_143253