%0 Journal Article
%A William L. Paschke
%T A numerical invariant for finitely generated groups via actions on graphs.
%J Mathematica Scandinavica
%D 1993
%P 148-160
%V 72
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MS2_1993__72_1_167243/
%F MS2_1993__72_1_167243