Hudson, Richard H. (1976), "Generalizations of a classical theorem in number theory", Mathematics of Computation, 30 (135): 649–656, doi:10.2307/2005336, MR0404112
Hudson, Richard H. (1976), "Generalizations of a classical theorem in number theory", Mathematics of Computation, 30 (135): 649–656, doi:10.2307/2005336, MR0404112