%0 Journal Article
%A Williams, Kenneth S.
%T On A Theorem of Niven
%J Canadian mathematical bulletin
%D 1967
%P 573-578
%V 10
%N 4
%U http://geodesic.mathdoc.fr/articles/10.4153/CMB-1967-055-3/
%R 10.4153/CMB-1967-055-3
%F 10_4153_CMB_1967_055_3