1. P.J. Stang, Chem. Rev. 78, 383 (1978)
2. W. Kirmse, Carbene Chemistry, 2nd edn. (Academic, New York, 1971)
3. R.A. Moss, Carbenes, vol. I/II (Wiley, New York, 1975)
4. C. Wentrup, Reactive Molecules (Wiley, New York, 1984)
5. M.P. Doyle, D.C. Forbes, Chem. Rev. 98, 911 (1998)