Let a Group have a presentation
so that , where is the Free Group with basis
and is the
Normal Subgroup generated by the . If is a Group with
for all , then there is a surjective homomorphism with
See also Free Group, Normal Subgroup
Rotman, J. J. An Introduction to the Theory of Groups, 4th ed. New York: Springer-Verlag, p. 346, 1995.
© 1996-9 Eric W. Weisstein