TY - JOUR AU - Rudwaleit, M; Landewé, R; van der Heijde, D TI - The Development of Assessment of SpondyloArthritis international Society (ASAS) Classification Criteria for Axial Spondyloarthritis (Part I): Classification of paper patients by expert opinion including uncertainty appraisal JO - Ann Rheum Dis VL - 68 PY - 2009 DO - 10.1136/ard.2009.108217 SP - 770 EP - 776 N1 - et al. ER -