Disease activity in systemic lupus erythematosus: report of the Consensus Study Group of the European Workshop for Rheumatology Research. I. A descriptive analysis of 704 European lupus patients - Vitali, C; Bencivelli, W; Isenberg, D A (Clin Exp Rheumatol, 1992)
, et al; European Consensus Study Group for Disease Activity in SLE.