@article{2426, author = {Morgado, Jos\'e}, title = {On the arithmetical function $\sigma \_k^*$ }, journal = {Portugaliae mathematica}, volume = {23}, year = {1964}, pages = {35-40}, zbl = {0146.05203}, mrnumber = {0173652}, language = {en}, url = {http://dml.mathdoc.fr/item/2426} }
Morgado, José. On the arithmetical function $\sigma _k^*$ . Portugaliae mathematica, Tome 23 (1964) pp. 35-40. http://gdmltest.u-ga.fr/item/2426/