1. H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, in Ergebnisse der Mathematik und ihrer Grenzgebiete, Chapter 2, pp. 12–18.
2. Some Definitions of Klein's Simple Group of Order 168 and Other Groups;Leech;Proc. Glasgow Math. Assoc.,1962
3. An Algorithmic Solution for a Word Problem in Group Theory;Mendelsohn;Canad. J. Math.,1964
4. Correction to: An Algorithmic Solution for a Word Problem in Group Theory;Mendelsohn;Canad. J. Math.,1965
5. The Collineation Groups of Free Planes, II: A Presentation for the Group G2;Sandler;Proc. Amer. Math. Soc.,1965