1. Department of Clinical and Experimental Medicine, Division of Rheumatology, University of Florence, AOU Careggi, Florence, Italy
2. Department of Rheumatology A, Cochin Hospital and Cochin Institute, Assistance Publique-Hôpitaux de Paris, Paris-Descartes University, Paris, France
3. Department of Rheumatology and Immunology, University of Pécs, Pécs, Hungary
4. Department of Rheumatology, David Geffen School of Medicine, University of California. Los Angeles, Los Angeles, CA
5. Department of Medicine, University of Michigan Scleroderma Program, University of Michigan, Ann Arbor, MI, USA