1. D. M. Poole and P. M. Thomas, Proc. Symp. Electron Microprobe (Washington 1964), New York: Wiley. 1966. p. 269.
2. R. Theisen, Quantitative Electron Microprobe Analysis. Berlin: Springer-Verlag. 1965.
3. P. Duncumb and P. K. Shields, in The Electron Microprobe, New York: Wiley. 1966. p. 284.
4. K. F. J. Heinrich, Advan. X-Ray Anal.11, 40 (1968).
5. D. R. Beaman, Analyt. Chemistry39, 418 (1967).