1. Comprehensive Pneumology CenterHelmholtz Center MunichUniversity Hospital GrosshadernLudwig Maximilians University MünchenMunichGermany
2. Division of Pulmonary Sciences and Critical Care MedicineDepartment of MedicineUniversity of ColoradoDenverColoradoUSA
3. Department of Internal MedicineUniversity of Giessen Lung CenterGiessenGermany