1. Department of Finance and Accounting, EBS Universität für Wirtschaft und Recht, Wiesbaden, Germany
2. Faculty of Pure and Applied Mathematics, Wroclaw University of Science and Technology, Wroclaw, Poland
3. Department of Mathematics, University of Wroclaw, Wroclaw, Poland
4. Department of Statistics, Lund University, Lund, Sweden
5. Department of Economics and Management, University of Trento, Trento, Italy