1. Satyendra Nath Bose National Centre for Basic Sciences, Block-JD, Salt Lake, Kolkata 700106, India
2. Department of Physics, Barasat Government College, Kolkata 700124, India
3. Saha Institute of Nuclear Physics, Kolkata 700064, India
4. St. Xaviers College, Mumbai 400001, India
5. Department of Physics, Raghunathpur College, Raghunathpur, Purulia 723133, India
6. Economic Research Unit, Indian Statistical Institute, Kolkata 700108, India