1. R. Omnès,Rev. Mod. Phys. 64, 339 (1992), is an exhaustive review of the field. W. H. Zurek,Phys. Today 44(10), 36 (1991), is a pedagocical introduction; see also letters about this article and Zurek’s reply in:Phys. Today 46(4), 13 (1993).
2. W. Heisenberg,The Physicists Conception of Nature (Hutchinson, London, 1958).
3. L. E. Ballentine,Rev. Mod. Phys. 42, 358 (1970).
4. N. Bohr,Atomic Theory and the Description of Human Knowledge (Cambridge University Press, Cambridge, 1934), p. 19.
5. J. von Neumann,Mathematical Foundations of Quantum Mechanics (Princeton University Press, Princeton, 1955), Chap. VI.