1. E.W. Adams and E.C. Benson, Nim-type games, Carnegie Inst. Tech., Report 13, 1956.
2. Dean Thomas Allemang, Machine Computation with Finite Games, M.Sc. thesis, Cambridge, England, 1984.
3. Richard Bruce Austin, Impartial and Partisan Games, M.Sc. thesis, University of Calgary, 1976.
4. W.W. Rouse Ball (revised H.S.M. Coxeter), Mathematical Recreations and Essays, 11th edition, Macmillan, New York, 1939, p. 40.
5. W.W. Rouse Ball and H.S.M. Coxeter, Mathematical Recreations and Essays, 12th edition, University of Toronto Press, Toronto, 1974; reprinted Dover, New York, 1987; pp. 36–40.