Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MS2_1960__8_165732, author = {Eckford Cohen}, title = {Nagell's {Totient} {Function.}}, journal = {Mathematica Scandinavica}, pages = {55--58}, publisher = {mathdoc}, volume = {8}, year = {1960}, zbl = {0100.03804}, url = {http://geodesic.mathdoc.fr/item/MS2_1960__8_165732/} }
Eckford Cohen. Nagell's Totient Function.. Mathematica Scandinavica, Tome 8 (1960), pp. 55-58. http://geodesic.mathdoc.fr/item/MS2_1960__8_165732/