TY  - JOUR
AU  - Florian Luca
AU  - Carl Pomerance
TI  - On some problems of M/akowski–Schinzel and Erdős
concerning the arithmetical functions $\phi $ and $\sigma $
JO  - Colloquium Mathematicum
PY  - 2002
SP  - 111
EP  - 130
VL  - 92
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.4064/cm92-1-10/
DO  - 10.4064/cm92-1-10
LA  - en
ID  - 10_4064_cm92_1_10
ER  -