Gupta S., Pradhan J., . (1987). Text book of physics. Jalandhar City: Suraj Kapur.
Gupta S.K, Pradhan J.M, . 1987. Text book of physics. Jalandhar City: Suraj Kapur.
Gupta S.K, Pradhan J.M, . Text book of physics. Jalandhar City: Suraj Kapur. 1987.
