1. Department of Mathematics and Computer Science, Faculty of Science, Port Said University, Port Said, Egypt
2. Department of Mathematics, College of Science, Qassim University, P.O. Box 6644, Buraydah 51452, Saudi Arabia
3. Department of Mathematics, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt
4. Department of Mathematical Science, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 105862, Riyadh 11656, Saudi Arabia