Classification, categorization and essential items for digital ulcer evaluation in systemic sclerosis: a DeSScipher/European Scleroderma Trials and Research group (EUSTAR) survey oleh J. Blagojevic, S. Bellando-Randone, G. Abignano, J. Avouac, L. Cometi, L. Czirják, C. P. Denton, O. Distler, M. Frerix, S. Guiducci, D. Huscher, V. K. Jaeger, V. Lóránd, B. Maurer, S. Nihtyanova, G. Riemekasten, E. Siegert, I. H. Tarner, S. Vettori, U. A. Walker, Y. Allanore, U. Müller-Ladner, F. Del Galdo, M. Matucci-Cerinic, EUSTAR co-workers