1. R. Carter, Finite Groups of Lie type: Conjugacy Classes and Complex Characters, Wiley, Chichester, 1985.
2. D. Chillag and A. Mann, Nearly odd-order and nearly real finite groups, Communications in Algebra 26 (1998), 2041–2064.
3. J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker, and R. A. Wilson, An ATLAS of Finite Groups, Clarendon Press, Oxford, 1985.
4. R. Dipper and J. Du, Harish-Chandra vertices, Journal für die Reine und Angewandte Mathematik 437 (1993), 101–130.
5. S. Dolfi, G. Navarro and Pham Huu Tiep, Primes dividing the degrees of the real characters of finite groups, Mathematishce Zeitschrift 259 (2008), 755–774.