1. A. Aspect, P. Grangier and G. Roger: Phys. Rev. Lett 47, 460–463 (1981)
2. J.S. Bell: Physics 1, 195–200 (1964); reprinted: J.S. Bell: Speakable and Unspeakable in Quantum Mechanics. Cambridge Univ. Press, 1987
3. J.S. Bell: Physics World (August 1990)
4. N. Bohr: In: P.A. Schillp (ed.): Albert Einstein: Philosopher-Scientist (The Library of Living Philosophers Evanston, IL) 1949, p. 200. A copy can be found at the web site (http://www.emr.hibu.no/lars/eng/schlipp/Default.html)
5. N. Bohr: Atomic Physics and Human Knowledge. Wiley, New York 1958