1. M. Aschbacher. Sporadic groups (Cambridge University Press, 1994).
2. J. N. Bray.Symmetric presentations of sporadic groups and related topics. Ph.D. thesis. University of Birmingham (1997).
3. J. Cannon and C. Playoust. An introduction to MAGMA (School of Mathematics and Statistics, University of Sydney, 1993).
4. J. H. Conway.Three lectures on exceptional groups. In Finite simple groups (Academic Press, 1970), pp. 215-247.
5. J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson.An atlas of nite groups (Oxford University Press, 1985).