1. Division of Rhinology and Skull Base Surgery, Department of Otolaryngology – Head & Neck Surgery Mayo Clinic Rochester Minnesota USA
2. Department of Otolaryngology – Head & Neck Surgery Thomas Jefferson University Philadelphia Pennsylvania USA
3. Division of Rhinology and Endoscopic Skull Base Surgery, Department of Otolaryngology – Head & Neck Surgery Stanford University Palo Alto California USA
4. Department of Otolaryngology – Head & Neck Surgery University of Oklahoma Health Sciences Center Oklahoma City Oklahoma USA
5. Department of Otolaryngology – Head & Neck Surgery Mount Sinai School of Medicine New York New York USA
6. Division of Rhinology, Allergy and Skull Base Surgery, Department of Otolaryngology – Head & Neck Surgery University of North Carolina Chapel Hill North Carolina USA
7. Department of Otolaryngology – Head & Neck Surgery University of Pittsburgh Medical Center Pittsburgh Pennsylvania USA