1. BLOOMFIELD, A. L. (1956). A.M.A. Arch. intern. Med., 98, 288.
2. CALZAOLARI, C., and BORGHERESI, S. (1956). Riv. Clin. pediat., 57, 846. 1 fig, 12 refs.
3. LANZA, I., and MORBIDELLI, R. (1956). Minerva pediat. (Torino), 8, 1131. 41 refs.
4. STECHER, R. S. (1956). Rev. esp. Reum., 6, 446.
5. BANERJEE, J. C. (1956). Indian Heart J., 8, 39. 11 refs.