Institution: | 1. Department of Mathematics, Lahore University of Management Sciences, 54792-Lahore, Pakistan;2. Department of Mathematics, Statistics and Physics, Qatar University, Doha 2713, Qatar;3. Department of Mathematics and Statistics, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia;4. Department of Mathematical Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA |