BHATTACHARYA, S. N. “Change in Rayleigh Wave Phase Velocity Due to Decrease of P-Wave Velocity before an Earthquake”. MAUSAM 30, no. 2 & 3 (April 1, 1979): 335–336. Accessed November 22, 2024. http://103.215.208.102/index.php/MAUSAM/article/view/3049.