Elements of Mathematics. Lie Groups and Lie Algebras
The book is one of the Bourbaki volumes, translated into English. The first three chapters of the book contain part of a theory needed in a study of Lie groups and Lie algebras. Chapter 4 is devoted to Coxeter groups and Tits systems. Chapter 5 contains a discussion of groups generated by reflections. Finally, Chapter 6 treats root systems, ending with their classification.