1. Department of Basic Science, Preparatory Year Deanship, King Faisal University, Hofuf, Al-Ahsa, Saudi Arabia
2. Department of Mathematics, College of Science, Majmaah University, Al Majmaah, Saudi Arabia
3. Department of Mathematics, Faculty of Science, Mansoura University, Mansoura, Egypt
4. Faculty of Business Administration, Delta University of Science and Technology, Egypt
5. Faculty of Business Administration, Taibah University, Khyber, Saudi Arabia