1. Colin Campbell, George Havas, Stephen Linton, and Edmund Robertson, Symmetric presentations and orthogonal groups, The Atlas of Finite Groups: Ten Years On (Birmingham, 1995), London Math. Soc. Lecture Note Ser., vol. 249, Cambridge Univ. Press, Cambridge, 1998, pp. 1–10.[MR]
  2. Colin M. Campbell, George Havas, Colin Ramsay, and Edmund F. Robertson, Nice efficient presentations for all small simple groups and their covers, LMS J. Comput. Math. 7 (2004), 266–283 (electronic).[MR]
  3. Colin M. Campbell, George Havas, Colin Ramsay, and Edmund F. Robertson, On the efficiency of the simple groups of order less than a million and their covers, Experiment. Math. 16 (2007), no. 3, 347–358.[MR]
  4. Colin M. Campbell, George Havas, and Edmund F. Robertson, Addendum to: "An elementary introduction to coset table methods in computational group theory", Groups—St. Andrews 1981, London Math. Soc. Lecture Note Ser., vol. 71, Cambridge Univ. Press, Cambridge, 2007, pp. 361–364.[MR]
  5. Marston Conder, Edmund Robertson, and Peter Williams, Presentations for 3-dimensional special linear groups over integer rings, Proc. Amer. Math. Soc. 115 (1992), no. 1, 19–26.[MR]
  6. George Havas and Edmund F. Robertson, Two groups which act on cubic graphs, Computational Group Theory (Durham, 1982), Academic Press, London, 1984, pp. 65–68.[MR]
  7. George Havas and Edmund F. Robertson, Application of computational tools for finitely presented groups, Computational support for discrete mathematics (Piscataway, NJ, 1992), DIMACS Ser. Discrete Math. Theoret. Comput. Sci., vol. 15, Amer. Math. Soc., Providence, RI, 1994, pp. 29–39.[MR]
  8. George Havas and Edmund F. Robertson, Central factors of deficiency zero groups, Comm. Algebra 24 (1996), no. 11, 3483–3487.[MR]
  9. George Havas, Edmund F. Robertson, and Dale C. Sutherland, Behind and beyond a theorem on groups related to trivalent graphs, J. Aust. Math. Soc. 85 (2008), no. 3, 323–332.