1. DADU, University of Sassari, Palazzo Pou Salit, Alghero 07041, SS, Italy e-mail:
2. DICAAR, University of Cagliari, Via Marengo 2, Cagliari 09100, Italy e-mail:
3. DII, University of Padova, Via Venezia 1, Padova 35131, Italy e-mail:
4. G.F.T.A (Technical Physics Association), via G. Zurita 13, Cagliari 09125, Italy e-mail:
5. DADI, Università degli Studi della Campania “Luigi Vanvitelli”, Abbazia di San Lorenzo ad Septimum, via S. Lorenzo, Aversa 81031, CE, Italy e-mail: