Affiliation: | aDepartment of Mathematics, University of Crete and Institute of Applied and Computational Mathematics, FORTH, Heraklion 71110, Greece;bDepartment of Applied Mathematics, University of Crete and Institute of Applied and Computational Mathematics, FORTH, Heraklion 71110, Greece;cAthens University of Economics and Business, 76 Patission Street, Athens 104 34, Greece;dTSC, Tilburg University, The Netherlands |