%0 Journal Article
%A E.M. Stein
%T An Example on the Heisenberg Group Related to the Levy Operator.
%J Inventiones mathematicae
%D 1982
%P 209-216
%V 69
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM_1982__69_142948/
%F IM_1982__69_142948