@article{1255989007, author = {Lam, T. Y.}, title = {On the number of solutions of $x^{p^{k}}=a$ in a $p$-group}, journal = {Illinois J. Math.}, volume = {32}, number = {4}, year = {1988}, pages = { 575-583}, language = {en}, url = {http://dml.mathdoc.fr/item/1255989007} }
Lam, T. Y. On the number of solutions of $x^{p^{k}}=a$ in a $p$-group. Illinois J. Math., Tome 32 (1988) no. 4, pp. 575-583. http://gdmltest.u-ga.fr/item/1255989007/