1. Abresch, K., u. W. Dobner: Arch. Eisenhüttenwes. 29, 25 (1958).
2. Alkemade, C. T. J.: Proc. of the Sixth International Conference on Spectroscopy, p. 7 (1956).
3. Alkemade, C. T. J., u. M. E. J. Jeuken: diese Z. 158, 401 (1957).
4. Cencely, J.: Proc. of the Sixth International Conference on Spectroscopy, p. 62 (1956).
5. Fa. Electronest, Saarbrücken, Druckschrift.