@article{GDZPPN002401193, title = {Counting Finite Groups of Given Order.}, journal = {Mathematische Zeitschrift}, volume = {99}, year = {1967}, pages = {236-237}, zbl = {0189.02304}, url = {http://dml.mathdoc.fr/item/GDZPPN002401193} }
Gallagher, Patrick X. Counting Finite Groups of Given Order.. Mathematische Zeitschrift, Tome 99 (1967) pp. 236-237. http://gdmltest.u-ga.fr/item/GDZPPN002401193/