1. Department of Applied Mathematics with Oceanology and Computer Programming, Vidyasagar University, Midnapore 721 102, India
2. Department of Mathematics, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
3. Department of Mathematics, Government College University Faisalabad, Faisalabad 38000, Pakistan
4. Department of Mathematics, Jahangirnagar University, Savar, Dhaka, Bangladesh