1. King Abdulaziz University, Faculty of Science, Department of Mathematics, Research Group, Jeddah, Saudi Arabia
2. University of Valladolid, E.T.S.I. of Telecomunications, Department of Applied Mathematics, Valladolid, Spain
3. King Abdulaziz University, Faculty of Science, Department of Mathematics, Research Group, Jeddah, Saudi Arabia + Université de La Rochelle, Faculté des Sciences, Laboratoire de Mathèmatiques, Image et Applications, La Rochelle, France