1. Aston, F. W. (1924) Isotopes, Edward Arnold & Co., London.
2. Futrell, J. H. (1996) Proceedings of the 44th ASMS Conference on Mass Spectrometry and Allied Topics, Portland, Oregon, 34.
3. Nier, A. O. C. Int. J. Mass Spectrom. Ion Processes 100, 1–13.
4. Svec, H. J. (1985) Int. J. Mass Spectrom. Ion Processes 66, 3–29.
5. Cooks, R. G., Beynon, J. H., and Caprioli, R. M. (1973) Metastable Ions, Elsevier, Amsterdam, The Netherlands.