%0 Journal Article
%A Kevin Ford
%T The number of solutions of $\varphi (x)=m$
%J Annals of mathematics
%D 1999
%V 150
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/AM_1999_150_1_a7/
%F AM_1999_150_1_a7