Matteo Gaeta Nicola Capuano Angelo Gaeta Francesco Orciuoli Laura Pappacena Pierluigi Ritrovato DIOGENE: A service Oriented Virtual Organisation for e-Learning. 145-158 2005 Towards the Learning Grid conf/lege/2005 db/conf/lege/faia127.html#GaetaCGOPR05 http://www.booksonline.iospress.nl/Content/View.aspx?piid=1267