@article{JIS_2016__19_3_a5,
     author = {Ransford,  Julian},
     title = {A sum of gcd's over friable numbers},
     journal = {Journal of integer sequences},
     year = {2016},
     volume = {19},
     number = {3},
     zbl = {1415.11120},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2016__19_3_a5/}
}