1. Mathematics Department, Faculty of Science, Tanta University, 31511 Tanta, Egypt
2. Section of Mathematics, International Telematic University Uninettuno, 001186 Roma, Italy
3. Mathematics Department, Faculty of Education, Ain-Shams University, 11566 Cairo, Egypt
4. Mechanical Engineering Department, College of Engineering and Islamic Architecture, Umm Al-Qura University, 5555 Makkah, Saudi Arabia. Email: aiismail@uqu.edu.sa