1. Bancroft, G. M., Adams, I., Coatsworth, L. L., Bennewitz, C. D., Brown, J. D., Westwood, W. D.: Anal. Chem. 47, 586 (1975)
2. Kainz, G., Sontag, G.: Fresenius Z. anal. Chem. 269, 267 (1974)
3. Kraft, G., Dosch, H.: Fresenius Z. anal. Chem. 281, 97 (1976)
4. Kraft, G., Fischer, H.: Indikation von Titrationen, p. 154. Berlin-New York: De Gruyter 1972
5. Siegbahn, K., Nordling, C., Fahlman, A., Nordberg, R., Hamrin, K., Hedman, J., Johansson, G., Bergmark, T., Karlsson, S.-E., Lindgren, I., Lindberg, B.: ESCA-Atomic, molecular and solid state structure studied by means of electron spectroscopy, Nova Acta Regiae Soc. Sci. Upsaliensis, Ser. IV, Vol. 20 (1967)