1. A simple method of estimating clot retraction, with a survey of normal values and the changes that occur with menstruation;Ackroyd;Clin. Sci.,1949a
2. The mechanism of the reduction of clot retraction by sedormid in the blood of patients who have recovered from sedormid purpura;Ackroyd;Clin. Sci.,1949b
3. Actively acquired tolerance of foreign cells;Billingham;Nature,1953
4. Colover , J. 1961 Proc. Ass. din. Path