1. Chaps. 4–6;Bourbaki,1981
2. C. K. Fan, A Hecke Algebra Quotient and Properties of Commutative Elements of a Weyl Group, Ph. D. thesis, Massachusetts Institute of Technology, 1995.
3. Nilpotent orbits and commutative elements;Fan;J. Algebra,1997
4. Reflection Groups and Coxeter Groups;Humphreys,1990
5. Infinite Dimensional Lie Algebras;Kac,1990