@article{1255629822, author = {Hobby, Charles R.}, title = {The derived series of a finite $p$-group}, journal = {Illinois J. Math.}, volume = {5}, number = {1}, year = {1961}, pages = { 228-233}, language = {en}, url = {http://dml.mathdoc.fr/item/1255629822} }
Hobby, Charles R. The derived series of a finite $p$-group. Illinois J. Math., Tome 5 (1961) no. 1, pp. 228-233. http://gdmltest.u-ga.fr/item/1255629822/