1. Klinik für Hals-, Nasen-, Ohren-Krankheiten, Hals-und Gesichtschirurgie, Kantonsspital Aarau, Switzerland
2. Klinik für Mund- Kiefer- und Gesichtschirurgie, Universitätsmedizin Charit Berlin, Berlin, Germany
3. Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
4. Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
5. Division of Otolaryngology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
6. Department of Otolaryngology and Communications Enhancement, Boston Children’s Hospital, Boston, Massachusetts, USA