1. Department of Statistics, Government Associate College, Khairpur Tamewali, Bahawalpur, Pakistan
2. Department of Mathematics, College of Science, P.O. Box 11099, Taif University, Taif 21944, Saudi Arabia
3. Department of Mathematics (Statistics Option) Programme, Pan African University, Institute of Basic Science, Technology and Innovation (PAUSTI), Nairobi 6200-00200, Kenya
4. Department of Mathematics, Faculty of Science, Mansoura University, Mansoura 35516, Egypt