1. The Biosynthesis of Vitamins and Related Compounds;GOODWIN,1963
2. E. E. SNELL, Proc. 4th International Congress of Biochemistry, Vol. 11, Pergamon, Oxford, 1959, p. 250.
3. E. E. SNELL, Proc. 5th International Congress of Biochemistry, Vol. 4, Pergamon, Oxford, 1963, p. 268.