Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{PORMA_1973__32_3_115202, author = {Shader, Leslie E.}, title = {Closed form expressions for several {Ramanujan} sums}, journal = {Portugaliae mathematica}, pages = {147--153}, publisher = {mathdoc}, volume = {32}, number = {3}, year = {1973}, mrnumber = {0314805}, zbl = {0256.10003}, language = {en}, url = {http://geodesic.mathdoc.fr/item/PORMA_1973__32_3_115202/} }
Shader, Leslie E. Closed form expressions for several Ramanujan sums. Portugaliae mathematica, Tome 32 (1973) no. 3, pp. 147-153. http://geodesic.mathdoc.fr/item/PORMA_1973__32_3_115202/