1. Hypermaps and Symmetry;Breda d'Azevedo,1991
2. The refexible hypermaps of characteristic—2;Breda d'Azevedo;Math Slovaca,1997
3. Regular maps on non-orientable surfaces;Conder;Geom. Dedicata,1995
4. M. Conder, S.E. Wilson, Inner reflectors, to appear.
5. Generators and Relations for Discrete Groups;Coxeter,1972