1. Institute of Ground Water Studies, Faculty of Natural and Agricultural Sciences, University of the Free State, South Africa
2. Department of Basic Sciences and Related Studies, Mehran University of Engineering and Technology, Jamshoro, Pakistan
3. Department of Physics, College of Science, King Faisal University, Al Ahsa, Saudi Arabia
4. Laboratory of Fluid Mechanics, Physics Department, Faculty of Science of Tunis, University of Tunis Ei Manar, Tunis, Tunisia
5. Department of Mathematics, Government College University, Hyderabad, Pakistan