ZIÓŁKOWSKI, W., and A. ŚLIWIŃSKI. “Application of a Vibrational Impedance Head to the Measurement of the Complex Elastic Modulus by the Driving Point Impedance Method”. Archives of Acoustics, vol. 16, no. 3-4, May 2014, pp. 591-07, https://acoustics3.ippt.pan.pl/index.php/aa/article/view/1252.