First Author:   Refk Selmi Tunis Business School s.refk@yahoo.fr         Second Author: Jamal Bouoiyour University of Pau jamal.bouoiyour@univ-pau.fr         Third Author: Aviral Kumar Tiwari IFHE University IBS Hyderabad aviral.eco@gmail.com         Fourth Author: Olaolu Richard Olayeni Obafemi Awolowo University rolayeni@gmail.com