1. W. E. Dasent, “Nonexistent Compounds,” Marcel Dekker, New York, N.Y., 1965, Chapter 4.
2. L. E. Gusel’nikov, N. S. Nametkin, and V. M. Vdovin,Russ. Chem. Rev.,43, 620 (1974).
3. L. E. Gusel’nikov, N. S. Nametkin, and V. M. Vdovin,Account Chem. Res.,8, 18 (1975).
4. P. Jutzi,Angew. Chem. Int. Ed. Engl.,14, 232 (1975).
5. For an excellent and extensive, although somewhat old, discussion of bonding in Group IVB chemistry, see E. A. V. Ebsworth, in “Organometallic Compounds of the Group IV Elements,” A. G. MacDiarmid, Ed., Marcel Dekker, New York, N.Y., 1968.