1. Wright, J. G., and Hall, L. W., Veterinary Anæsthesia, fifth ed., 209 (Baillière, Tindall and Cox, London, 1961).
2. Adrian, E. D., and Moruzzi, G., J. Physiol., 97, 153 (1939).
3. Hill, D., and Parr, G., Electroencephalography, first ed., 184 (MacDonald, London, 1950).
4. Grieg, J. R., Hoare's Veterinary Medicine and Therapeutics, fifth ed., 194 (Baillière, Tindall and Cox, London, 1933).
5. Shukla, R. C., et al., Indian J. Physiol., 16, 17 (1962).