[CS] J.H. Conway, N.J.A. Sloane, Sphere packings, Lattices and Groups, Springer-Verlag, New York, 1988.

[MS] F. J. MacWilliams and N. J. A. Sloane, The Theory of Error-Correcting Codes, North-Holland, Amsterdam, 1977.

[P1] V. Pless, Introduction to the Theory of Error-Correcting Codes, second edition, Wiley, New York, 1989.

[P2] V. Pless, Decoding the Golay codes, IEEE Trans. Info. Theory 32 (1986), 561-567.

[Cu] R. T. Curtis, Geometric interpretations of the 'natural' generators of the Mathieu groups, Math. Proc. Camb. Phil. Soc. 107 (1990), 19-26.