1. Beilstein,Handbuch der Organische Chemie, 4th Edition, Band XVII, 1933, p 268.
2. C. S. Gibson and J. L. Simonsen,Jour. Chem. Soc., 1928, 2307.
3. A. Bayer,Ber., 1910,43, 2337.
4. A. A. Boon, F. J. Wilson and I. M. Heilbron,Jour. Chem. Soc., 1914,105, 2177. A. Hantsch,Ber., 1919,52, 1535. R. C. Gibbs, J. R. Johnson and E. C. Hughes,Jour. Amer. Chem. Soc., 1930,52, 4895.
5. R. Robinson,Outline of an Electrochemical Theory of Course of Organic Reactions. Institute of Chemistry Lecture, 1932.