@article{GDZPPN002407833, title = {The Number of Conjugacy Classes in a Finite Group.}, journal = {Mathematische Zeitschrift}, volume = {114}, year = {1970}, pages = {175-179}, zbl = {0221.20006}, url = {http://dml.mathdoc.fr/item/GDZPPN002407833} }
Gallagher, Patrick X. The Number of Conjugacy Classes in a Finite Group.. Mathematische Zeitschrift, Tome 114 (1970) pp. 175-179. http://gdmltest.u-ga.fr/item/GDZPPN002407833/