Square free values of the order function. Pappalardi, Francesco — 2003 The New York Journal of Mathematics [electronic only]
On the exponent of the ideal class groups of imaginary extensions of q ( x ) Hershy Kisilevsky; Francesco Pappalardi — 1995 Acta Arithmetica
Composite positive integers with an average prime factor Florian Luca; Francesco Pappalardi — 2007 Acta Arithmetica
Coincidences in the values of the Euler and Carmichael functions William D. Banks; John B. Friedlander; Florian Luca; Francesco Pappalardi; Igor E. Shparlinski — 2006 Acta Arithmetica