1. Widdowson, E. M., and McCance, R. A., Proc. Roy. Soc., B, 152, 188 (1960).
2. Dobbing, J., Proc. Roy. Soc., B, 159, 503 (1963).
3. Chase, H. P., Dorsey, J., and McKhann, G. M., Pediatrics, 40, 551 (1967).
4. Benton, J. W., Moser, H. W., Dodge, P. R., and Carr, S., Pediatrics, 38, 801 (1966).
5. Howard, E., J. Neurochem., 12, 181 (1965).