1. Herrmann, K.: Arch. Pharm.291, 238 (1958).
2. Segal, B., Grager, W.: Nahrung11, 223 (1967).
3. Berger, W.-G., Herrmann, K. Diese Z.146, 266 (1971).
4. Vogt, E.: Weinchemie und Weinanalyse, 3. Aufl. Stuttgart: Ulmer 1969.
5. Singleton, V. L., Esau, P.: Phenolic substances in grapes and wine, and their significance. New York-London: Academic Press 1969.