@article{10_4153_CJM_1969_104_3,
     author = {Nasim, C.},
     title = {A {Summation} {Formula} {Involving} \ensuremath{\sigma}k(n), k > 1},
     journal = {Canadian journal of mathematics},
     pages = {951--964},
     year = {1969},
     volume = {21},
     number = {1},
     doi = {10.4153/CJM-1969-104-3},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1969-104-3/}
}