@article{1256048927, author = {Alperin, J. L.}, title = {Periodicity in groups}, journal = {Illinois J. Math.}, volume = {21}, number = {4}, year = {1977}, pages = { 776-783}, language = {en}, url = {http://dml.mathdoc.fr/item/1256048927} }
Alperin, J. L. Periodicity in groups. Illinois J. Math., Tome 21 (1977) no. 4, pp. 776-783. http://gdmltest.u-ga.fr/item/1256048927/