%0 Journal Article
%A K.S. Brown
%T Trees, valuations, and the Bieri-Neumann-Strebel invariant.
%J Inventiones mathematicae
%D 1987
%P 479-504
%V 90
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM_1987__90_143519/
%F IM_1987__90_143519