1. Department of Otorhinolaryngology, Rhinology and Skull Base Unit, Hospital ClinicUniversity of BarcelonaBarcelona Spain
2. Clinical Division of Otorhinolaryngology, Head and Neck SurgeryUniversity Hospitals LeuvenLeuven Belgium
3. ENT Department, Rhinology Unit and Smell Clinic, Clinical and Experimental Respiratory Immunoallergy, The August Pi i Sunyer Biomedical Research InstituteCenter for Biomedical Research in Respiratory DiseasesBarcelona Spain