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2. For a wealth of detail, consult the nSR web pages of: TRIUMF ( http://www.triumf.ca ), PSI ( http://www.psi.ch ), RAL-ISIS ( http://www.isis.rl.ac.uk /muons) and KEK-BOOM.
3. E.J. Ansaldo: Phys. Stat. Sol., A19 (1973) 11 (review).
4. E.N. Kaufman R.S. Raghavan, P. Raghavan, E.J. Ansaldo, R.A. Naumann: Phys. Rev. Lett., 34 (1975) 1558
5. H. Ackerman: In J. Christiansen (Ed.), Topics in Current Physics, Vol. 31, Springer, Berlin, 1983