1. Department of Mechanics, Biomechanics, and Mechatronics, Czech Technical University in Prague, Technická 4, 166 07 Prague 6, Czech Republic
2. Institute of Thermomechanics, Czech Academy of Sciences, Dolejškova 5, 182 00 Prague 8, Czech Republic
3. Speech and Voice Research Laboratory, Faculty of Social Sciences, Tampere University, Virta, Åkerlundinkatu 5, 33100 Tampere, Finland