1. Department of Applied sciences, KIET Group of Institutions Delhi-NCR, Ghaziabad, U.P.
2. Department of Mathematics, A.N.D. College Govindpuri, New Delhi
3. Research Scholar, Bhagwant University Ajmer (Rajasthan)
4. School of Sciences, UP Rajarshi Tandon Open University, Prayagraj, India, Department of ASH, B. K. Birla Institute of Engin. and Tech. Pilani (Raj.)