1. School of Science and Engineering, Al Akhawayn University in Ifrane, Ifrane, Morocco
2. Department of Mathematics, Faculty of Sciences University of Nouakchott, Nouakchott, Mauritania
3. LASTIMI Laboratory, High School of Technology-Sale, Mohammed V University, Rabat, Morocco
4. Mathematics Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia