In my undergraduate research project, I am going to study a paper on free products in division rings. To do this, however, I, of course, need to learn about free groups and free products.
Right now, the only reference I have is Rotman's "An Introduction to the Theory of Groups". Is this a good reference? Or is there a better book to get the intuition and the main theorems behind free groups?
Please have in mind that I am self-studying and that, being an undergrad, if it is possible to avoid too much Category Theory, it would be best.
Thanks in advance!
Try Magnus et al.'s, "Combinatorial Group Theory: Presentations of Groups in Terms of Generators and Relations". It's quite a comprehensive treatment of free groups and free products, alongside other concepts.
The following question of mine might be of interest too.
Different ways of constructing the free group over a set.