1. Department of Statistics, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
2. Department of Mathematics and Statistics, Indian Institute of Technology, Kanpur, Pin 208016, India
3. Mathematics Department, Faculty of Science, Damanhour University, Damanhour, Egypt
4. Mathematics and Statistics Department, College of Science, Taif University, PO Box 11099, Taif 21944, Saudi Arabia
5. Mathematics and Statistics Department, Sohag University, Sohag, Egypt