1. Otto Wagner HospitalVienna, Austria
2. Ludwig Boltzmann Institute for COPD and Respiratory EpidemiologyVienna, Austria
3. CIBER Enfermedades RespiratoriasBarcelona, Spain
4. Institut d’Investigacions Biomediques August Pi I SunyerBarcelona, Spain
5. Sigmund Freud UniversityVienna, Austria
6. Maastricht University Medical CenterMaastricht, the Netherlands
7. Paracelsus UniversitySalzburg, Austria
8. Maastricht UniversityMaastricht, the Netherlandsand
9. Hospital Clinic, University of BarcelonaBarcelona, Spain