1. G. Favrel, Bull. sci. pharmacol.20, 337 (1913); zitiert nach Chem. Zbl.1913, III, 576.
2. F. Feigl, Chemistry of Specific, Selective and Sensitiv Reactions. New York: Academic Press. 1949.
3. R. Pietsch, Mikrochim. Acta [Wien]1957, 161.
4. N. Uhlinger undN. Cook, J. Ind. Eng. Chem.11, 105 (1919).