@InCollection{Porcu:2008,
author
=
"E.Porcu and J.Matkowski and J.Mateu",
title
=
"Quasi arithmetic covariance functions and their possible reducibility through functional equations",
pages
=
"155--180",
year
=
"2008",
booktitle
=
"Positive definite functions: from Schoenberg to space-time challenges ISBN: 9788461282821",
editor
=
"ed. J. Mateu, E. Porcu",
publisher
=
"Publications de la Universitat Jaume I",
address
=
"Castelló de la Plana",
}