1. Department of Otorhinolaryngology – Head and Neck Surgery, Kuopio University Hospital and University of Eastern Finland, Kuopio, Finland
2. Department of Otorhinolaryngology – Head and Neck Surgery, Kuopio University Hospital, Kuopio, Finland
3. Skin and Allergy Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
4. Joensuun Uusi Apteekki and University of Eastern, Joensuu, Finland