@article{Grytczuk:2009,
author
=
"A.Grytczuk and F.Luca and M.Wójtowicz",
title
=
"On a conjecture of Makowski and Schinzel concerning the composition of the arithmetic functions \delta and \fi",
journal
=
"Colloquium Mathematicum",
volume
=
"Vol. 86",
number
=
"no 1",
pages
=
"31--36",
year
=
"2000",
}