1. R. Belcher undC. E. Spooner, J. Chem. Soc. London1943, 313.
2. M. O. Korshun undN. S. Sheveleva, Zhur. anal. Khim.11, 376 (1956).
3. V. A. Klimova undE. N. Merkulova, Izvest. Akad. Nauk SSSR, Otdel. Khim. Nauk1959, 781.
4. M. Ve?e?a, D. ?nobl undL. Synek, Mikrochim. Acta [Wien]1958, 9.
5. A. A. Abramyan undS. M. Atashyan, Izvest. Akad. Nauk Armyan. SSR, Khim. Nauki15, 521 (1962).