1. Institute of Acoustics, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznań, Poland
2. Hipolit Cegielski State University of Applied Sciences, Stefana Wyszyńskiego 38, 62-200 Gniezno, Poland
3. Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States