1. Mathematics Department, Faculty of Sciences, King Khalid University, Abha 9004, Saudi Arabia
2. Mathematics Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
3. Mathematics Department, Faculty of Sciences and Arts, King Khalid University, Dhahran Al Janoub, Saudi Arabia
4. Basic Science Department, Faculty of Computers and Informatics, Suez Canal University, Ismailia, Egypt