Week 10: Introduction to free groups, definition, examples and basic results
Massey W. S. (1991) Free Groups and Free Product of Groups. In: A Basic Course in Algebraic Topology. Graduate Texts in Mathematics, Vol 127. Springer, New York, NY.
Massey W. S. (1991) Free Groups and Free Product of Groups. In: A Basic Course in Algebraic Topology. Graduate Texts in Mathematics, Vol 127. Springer, New York, NY.