GHOSH , B. P., and S.N. SRIVASTAVA. “A O-200 Cps Frequency Converter For Audiomodulated Radiosonde”. MAUSAM 21, no. 2 (April 1, 1970): 295–302. Accessed November 22, 2024. http://103.215.208.102/index.php/MAUSAM/article/view/5390.