1. S. I. Ansari:
Department of statistics, Faculty of Science, University of Tabuk, Tabuk, Kingdom of Saudi Arabia, Department of Business Administration Azad Institute of Engineering and Technology, Lucknow, India
2. Rezk H.:
Mathematical Sciences Department, College of Science, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia. Department of Statistics, Al-Azhar University, Cairo, Egypt
3. Haitham M. Yousof:
Department of Statistics, Mathematics and Insurance, Benha University, Egypt