Chattopadhyay, A., and A. Chakraborty. “Sh Waves in a Porous Layer of Nonuniform Thickness”. Engineering Transactions 34, no. 1-2 (June 30, 1986): 3–13. Accessed January 17, 2026. http://et.ippt.gov.pl/index.php/et/article/view/1793.