1. Assistant Professor, Dept. of Mathematics, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, Hyderabad 500078, India (corresponding author).
2. Professor, Dept. of Applied Mathematics, Indian School of Mines, Dhanbad 826004, India.
3. Research Scholar, Dept. of Applied Mathematics, Indian School of Mines, Dhanbad 826004, India.