BANDERA, W., and K. PAWLACZYK. “Sound Velocity and Loss Factor of Polyurethane Composites. Part II”. Archives of Acoustics 16, no. 3-4 (December 31, 1991): 451–460. Accessed March 4, 2026. https://acoustics.ippt.gov.pl/index.php/aa/article/view/1241.