S. L. Gupta, S. Gupta, . (1999). Concepts Of Modern Physics. New Delhi: Dhanpat Rai Pub.
S. L. Gupta, S. Gupta, . 1999. Concepts Of Modern Physics. New Delhi: Dhanpat Rai Pub.
S. L. Gupta, S. Gupta, . Concepts Of Modern Physics. New Delhi: Dhanpat Rai Pub. 1999.