1. Westpfalz Klinikum
2. Westpfalz Klinikum, Kaiserslautern, Germany
3. University General Hospital of Alexandroupolis, Alexandroupolis, Greece
4. Inselspital, Bern University Hospital, University of Bern
5. Marienhospital Stuttgart
6. Internal Medicine II, Vienna University Hospital
7. Asklepios Lung Clinic Munich-Gauting
8. Patras University Hospital
9. University General Hospital of Alexandroupolis
10. Ruhrlandklinik, West German Lung Center, University Hospital Essen, University Duisburg-Essen