1. Kaehne, R. Ber. 1898, 31, 1048-1055. (b) Arbuzov, A. E. J. Russ. Phys. Chem. Soc. 1906, 38, 687.
2. (a) Michaelis, A.; Kaehne, R. Ber. 1898, 31, 1048-1055.
3. (b) Arbuzov, A. E. J. Russ. Phys. Chem. Soc. 1906, 38, 687.
4. Surmatis, J. D.; Thommen, R. J. Org. Chem. 1969, 34, 559-560.
5. Gillespie, P.; Ramirez, F.; Ugi, I.; Marquarding, D. Angew. Chem. Int. Ed. 1973, 12, 91-119. (Review).