1. Honegger, C.G., Helv. Chim. Acta46, 1772 (1963).
2. Berger, J.A., Meyniel, G., Petit, J. andBlanquet, P., Bull. Soc. Chim. France11, 2662 (1963); Compt. Rend.257, 1534 (1963).
3. Stahl, E., Chemie-Ing. Techn.36, 941–947 (1964).
4. Stahl, E. andVollmann, H., Talanta12, 525 (1965).
5. Abott, D.C. andThomson, J., Chem & Ind. (London)1965, 310.