Editorial
Authors
1 Universite d'Avignon, France.
2 Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran.
3 Departament d'Economia i d'Historia Economica, Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain.
4 School of Mathematics, Statistics and Computer Science, College of Science, University of Tehran, Enghelab Avenue, Tehran, Iran.