1. Hacettepe University Faculty of Medicine Ankara Turkey
2. UCSF Voice and Swallowing Center, Division of Laryngology, Department of Otolaryngology‐Head and Neck Surgery University of California San Francisco San Francisco California USA
3. Department of Otolaryngology‐Head and Neck Surgery University of Miami Miller School of Medicine and the USC Voice Center Miami Florida USA
4. Stockton Scientific Services Farmington Connecticut USA