@article{JIS_2011__14_6_a4,
     author = {Zhang, Deyu and Zhai, Wenguang},
     title = {Mean values of a class of arithmetical functions},
     journal = {Journal of integer sequences},
     publisher = {mathdoc},
     volume = {14},
     number = {6},
     year = {2011},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2011__14_6_a4/}
}