1. Department of Statistics, Quaid-I-Azam University, Islamabad, Pakistan
2. Department of Mathematics, College of Sciences and Arts (Muhyil), King Khalid University, Muhyil, Saudi Arabia
3. Department of Mathematics and Computer, College of Sciences, Ibb University, Ibb, Yemen
4. Department of Civil, Environmental and Natural Resources Engineering, Lulea University of Technology, Lulea, Sweden
5. Mathematics Department, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
6. Department of Statistics and Information, Sana’a University, Sana’a, Yemen
7. Department of Civil Engineering, College of Engineering, University of Diyala, Diyala Governorate, Iraq