1. [1] R. BRAUER, On a conjecture by Nakayama, Trans. Roy. Soc. Canad., III, 41 (1947), 11-19.
2. [2] R. BRAUER and C. NESBITT, On the modular characters of groups, Ann. of Math., 42, No.2 (1941), 556-590.
3. [3] L. DICKSON, History of the theory of numbers, Vol. I, New York, (1952).
4. [4] G. H. HARDY and E. M. WRIGHT, An introduction to the theory of numbers, Oxford (1954).
5. [5] D. E. LITTLEWOOD, The theory of group characters, Oxford (1950).