1. Eng., L. F., Chao, F. C., Gerstl, B., Pratt, D., and Tavaststjerna, M. G., Biochemistry, 7, 4455 (1968).
2. Alvord, E. C., in The Central Nervous System (edit. by Bailey, O. T., and Smith, D. E.), 52 (Williams and Wilkins, Baltimore, 1968).
3. Paterson, P. Y., Ann. Rev. Med., 20, 75 (1969).
4. Lumsden, C. E., Robertson, D. M., and Blight, R., J. Neurochem., 13, 127 (1966).
5. Carnegie, P. R., and Lumsden, C. E., Immunology, 12, 133 (1967).