1. Akhlaghi, Z.: On the average character degree of some ireeducible characters of a finite group, Math. Nachr., To appear
2. Bianchi, M., Chillag, D., Lewis, M.L., Pacifici, E.: Character degree graphs that are complete graphs. Proc. Amer. Math. Soc. 135(3), 671–676 (2007)
3. Conway, J.H., Curtis, R.T., Norton, S.P., Parker, R.A., Wilson, R.A.: ATLAS of finite groups. Oxford University Press, Clarendon, Oxford (1985)
4. Feit, W., Thompson, J.G.: Groups which have a faithful representation of degree less than $$(p-1)/2$$. Pacific J. Math. 11, 1257–1262 (1961)
5. Feit, W.: Groups which have a faithful representation of degree less than p-1. Trans. Amer. Math. Soc. 112, 287–303 (1964)