1. G. P. Ellis, in “Progress in Medicinal Chemistry” (G. P. Ellis and G. B. West, eds.), Vol. 6, pp, 322, Butterworths, London (1969).
2. J. M. Gulland and R. Robinson, Mem. Proc. Manchester Lit. Phil. Soc. 69, 79 (1925).
3. M. Gates and G. Tschudi, J. Amer. Chem. Soc. 74, 1109–1110 (1952); 78, 1380–1393 (1956).
4. J. Kalvoda, P. Buchschacher, and O. Jeger, Helv. Chim. Acta 38, 1847–1856 (1955); M. Mackay and D. C. Hodgkin, J. Chem. Soc. 1955, 3261–3267.
5. K. Goto, H. Yamasaki, I. Yamamoto, and R. Ohno, Proc. Jap. Acad. 33, 660 (1957).