1. ADAMS, R. D., and FOLEY, J. M. (1953), Res. Publ. Assn. Res. Nerv. Ment. Dis., 32, 198.
2. ATKINSON, M., BARNETT, E., SHERLOCK, S., and STEINER, R. E. (1955), Quart. J. Med., n.s. 24, 77.
3. BAUMANN, E. D. (1931), Janus 35, 153 and I85.
4. BENHAMOU, J. P., HARTMANN, L., and FAUVERT, R. (1955), Presse medicale, 63, 1451.
5. FINDLAY, G. M., and MARTIN, N. H. (1943), Lancet, i, 678.