Results of a multicentre study assessing the status of standardization of a recombinant thromboplastin for the control of oral anticoagulant therapy - Tripodi, A; Chantarangkul, V; Braga, M; Poller, L; ten Cate, J W; Van den Besselaar, AM HP; Mannucci, P M (Thromb Haemost, 1994)