1. Clements, F. W. andWishart, J. W., Metabolism5, 623 (1956).
2. Virtanen, A. I., Experientia17, 241 (1961).
3. Gmelin, R. andVirtanen, A. I., Acta chem. Scand.14, 507 (1960).
4. Gmelin, R. andVirtanen, A. I., Ann. Acad. Sci. Fennicae A II No.107 (1961).
5. Gmelin, R. andVirtanen, A. I., Suomen Kemistilehti B35, 34 (1962); Acta chem. Scand.16, 1378 (1962).