1. Guy's Hosp;CONYBEARE, J.;Gaz,1952
2. OSLER, W. (1910), Lancet, i, 697.
3. PATON, B. C. (1957), Amer. J. Med., 23, 76r.
4. RYLE, J. A., and RUSSELL, W. T. (1949), Brit. Heart J., I, 370.
5. STOCKS, P. (1951), Lancet, i, 35I. THOMAS, A. J., COCHRANE, A. L., and HIGGINS, I. T. T. (1958), Ibid., ii, 540.