1. Charité University Medicine, Department of Rheumatology and Clinical Immunology, Berlin, Germany
2. Mayo Clinic College of Medicine and Science, Division of Rheumatology, Rochester, Minnesota
3. Medical University Graz, Department of Rheumatology and Immunology, Graz, Austria
4. Hospital of Brunico (SABES-ASDAA), Department of Rheumatology, Brunico, Italy