@article{05723739,
title = {Mean values of a gcd-sum function over regular integers modulo },
journal = {Journal of Integer Sequences [electronic only]},
volume = {13},
year = {2010},
zbl = {1219.11143},
language = {en},
url = {http://dml.mathdoc.fr/item/05723739}
}
Zhang, Deyu; Zhai, Wenguang. Mean values of a gcd-sum function over regular integers modulo . Journal of Integer Sequences [electronic only], Tome 13 (2010) . http://gdmltest.u-ga.fr/item/05723739/