1. Sur les Groupes Hyperboliques d'après Mikhael Gromov;Ballman,1990
2. S.G. Brick, On Dehn functions and products of groups, Trans. Amer. Math. Soc., to appear.
3. Infinite groups as geometric objects;Gromov;Proc. I.C.M. Warszawa,1984
4. Semistability at ∞, ∞-ended groups and group cohomology;Mihalik;Trans. Amer. Math. Soc.,1987
5. Group Theory and Three-Dimensional Manifolds;Stallings,1971