1. Centre for Pneumology; Donaustauf Hospital; Ludwigstrasse 68 Donaustauf Germany
2. Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine; Ludwig-Maximilians-University; Munich Germany
3. Department of Medicine V, Haematology and Oncology; Friedrich Alexander University; Erlangen Germany
4. Division of Respirology; Department of Internal Medicine II; University of Regensburg; Regensburg Germany
5. Division of Pulmonary and Respiratory Medicine; Department of Internal Medicine III; RoMed Clinical Centre Rosenheim; Rosenheim Germany