PANUSZKA, R., and M. IWANIEC. “Current Trends of the Works on Acoustics Presented at the XLVI Open Seminar on Acoustics OSA’99”. Archives of Acoustics, vol. 25, no. 1, Jan. 2000, pp. 111-23, https://acoustics3.ippt.pan.pl/index.php/aa/article/view/358.