1. Uttaranchal University, Prem Nagar, Dehradun, India
2. Department of Physics, Gurukula Kangri Vishwavidyalaya, Haridwar, India
3. National Physical Laboratory (CSIR), K. S. Krishnan Marg, New Delhi, India
4. Department of Physics and Astrophysics, North Campus, University of Delhi, India
5. University of Petroleum & Energy Studies, Bidholi, Dehradun, India