Protein C deficiency in a controlled series of unselected outpatients: an infrequent but clear risk factor for venous thrombosis - Koster, T; Rosendaal, F R; Van der Meer, F J M; Colly, L P; Trienekens, P H; Poort, S R; Vandenbroucke, J P (Leiden Thrombophilia Study (LETS), 1995)
(in press)