Recommended Citation
Postprint version. Published in Naturwissenschaften, Volume 77, Issue 11, November 1, 1990, pages 536-538.
The definitive version is available at https://doi.org/10.1007/BF01139266.
Disciplines
Physics
Copyright
1990 Springer.
URL: https://digitalcommons.calpoly.edu/phy_fac/134