Rebuttal to the Letter by T. Exner and R. Dybkaer

• References

• 1 Loeliger EA, Lewis SM. Progress in laboratory control of oral anticoagulants. Lancet 1982; ii: 318-320
• 2 WHO Expert Committee on Biological Standardization. Thirty-third Report. WHO Tech Rep Ser 1983; 81-105
• 3 Van den Besselaar AMHP, Gralnick HR, Lewis SM. (eds) Thromboplastin Calibration and Oral Anticoagulant Control. Martinus Nijhoff Publishers; Boston, MA: 1984: 241-252
• 4 International Committee for Standardization in Haematology and International Committee on Thrombosis and Haemostasis. ICSH/ICTH recommendations for reporting prothrombin time in oral anticoagulant control. Thromb Haemostas 1985; 53: 155-156
• 5 Kirkwood TBL. Calibration of reference thromboplastins and standardization of the prothrombin time ratio. Thromb Haemostas 1983; 49: 238-244