1. Department of Business and Management Science , Bergen , Norway
2. Norwegian School of Economics , Bergen , Norway
3. Department of Mathematics , Bergen , Norway
4. University of Bergen , Bergen , Norway
5. Department of Psychiatry and Psychotherapy , , Regensburg , Germany
6. University of Regensburg , , Regensburg , Germany
7. Dipartimento di Giurisprudenza, Economia, Politica e Lingue Moderne (GEPLI) , , Rome , Italy
8. Libera Università Maria Ss Assunta , , Rome , Italy