%0 Journal Article
%A Karsten Grove
%A Detlef Gromoll
%T On Metrics on S2 All of Whose Geodesics Are Closed.
%J Inventiones mathematicae
%D 1981
%P 175-178
%V 65
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM_1981__65_142845/
%F IM_1981__65_142845