1. For the recent developments of molecular beam epitaxy, see the Proceedings of International Conference on Molecular Beam Epitaxy, published from J. Crys. Growth. (7th Conf., Schwabisch Gmund, 1992; 6th Conf., San Diego, 1990; 5th Conf., Sapporo, 1988)
2. See, for example, G. Bastard in Physics of Nanostructures (ed. by J.H. Davis and A.R. Long, Inst. of Physics 1992) 53–64
3. See, for example, H. Sakaki, ibid 1–20 (1992)
4. C. Weisbuch, R. Dingle, A.C. Gossard and W. Wiegmann, Solid State Commun. 38, 709(1981)
5. L. Goldstein, Y. Horikoshi, S. Tarucha and H. Okamoto, Jpn. J. Appl. Phys. 22, L1489 (1983)