@article{bwmeta1.element.desklight-9de2e566-57e4-437e-9cf6-dbb91e4da401,
author = {Carl Pomerance},
title = {On the composition of the arithmetic functions $\sigma$ and $\phi$},
journal = {Colloquium Mathematicae},
volume = {57},
year = {1989},
pages = {11-15},
zbl = {0695.10002},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.desklight-9de2e566-57e4-437e-9cf6-dbb91e4da401}
}
Carl Pomerance. On the composition of the arithmetic functions σ and φ. Colloquium Mathematicae, Tome 57 (1989) pp. 11-15. http://gdmltest.u-ga.fr/item/bwmeta1.element.desklight-9de2e566-57e4-437e-9cf6-dbb91e4da401/