1. Divison of Phoniatrics and Pediatric Audiology at the Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Erlangen, Medical School at Friedrich-Alexander University Erlangen-Nürnberg, Waldstrasse 1, 91054 Erlangen, Germany
2. Institute of Mechanics and Mechatronics, Technical University Vienna, Getreidemarkt 9, 1060 Vienna, Austria