Italy: University of Modena and Reggio Emilia, University of Messina, Faculty of Economics  / Germany: RWTH Aachen University / Serbia: Mathematical Institute of the Serbian Academy of Sciences and Arts / Albania: Unversity of Tirana/ Spain: Max Planck Society for the Advancement of Science, Spanish National Research Council / France Théorie Economique, Modélisation et Applications (ThEMA) University of Cergy-Pontoise.