A dose-ranging study of the oral direct thrombin inhibitor, ximelagatran, and its subcutaneous form, melagatran, compared with dalteparin in the prophylaxis of thromboembolism after hip or knee replacement: METHRO I MElagatran for THRombin inhibition in Orthopaedic surgery - Eriksson, BI; Arfwidsson, AC; Frison, L (Thromb Haemost, 2002)