1. School of Finance, Huainan Normal University, Huainan, 232038, P. R. China
2. School of Mathematics and Physics, Anhui Jianzhu University, Hefei, 230601, P. R. China
3. Department of Mathematics, COMSATS Institute of Information Technology, Lahore, 46000, Pakistan
4. Department of Mathematics, University of the Punjab, Lahore, Pakistan
5. Department of Applied Mathematics, Iran University of Science and Technology (IUST) Narmak, 16844, Tehran, Iran
6. School of Natural Sciences (SNS), National University of Sciences and Technology (NUST), Sector H-12, Islamabad, Pakistan