Lupus anticoagulant is the strongest risk factor for both venous and arterial thrombosis in patients with systemic lupus erythematosus – Comparison between different assays for the detection of antiphospholipid antibodies - Horbach, DA; Van Oort, E; Donders, RCJM; Derksen, RHWM; De Groot, PG (Thromb Haemost, 1996)