1. Department of Physics, Sardar Patel University, Vallabh Vidyanagar, India
2. Shree M R Arts & Science College, Rajpipla, India
3. Department of Applied Physics, The M. S. University of Baroda, Vadodara, India
4. Electronics Department, V.P. & R.P.T.P. Science College, Vallabh Vidyanagar, India