1. Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, via G Saragat 1, I-44122 Ferrara, Italy
2. Department of Structure Research of Condensed Matter, Institute of Nuclear Physics Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Kraków, Poland
3. Department of Theoretical Physics, University of Rzeszow, ul. Pigonia 1, 35-310 Rzeszów, Poland