H. RYFFERT, “XXVIII Open Seminar on Acoustics Gliwice, 7–11 September, 1981”, Arch. Acoust., vol. 7, no. 3-4, pp. 287–292, Mar. 2016, Accessed: Apr. 26, 2025. [Online]. Available: https://acoustics3.ippt.pan.pl/index.php/aa/article/view/3289