Lupus anticoagulant is the strongest risk factor for both venous and arterial thrombosis in patients with systemic lupus erythematosus - Horbach, D A; van, Oort E; Donders, R CJM; Derksen, R HWM; de, Groot PG (Comparison between different assays for the detection of antiphospholipid antibodies, 1996)