1. Crombie, L., and Elliott, M., Fortschr. Chem. org. NatStoffe, 19, 120 (1961).
2. Elliott, M., and Janes, N. F., in Pyrethrum the Natural Insecticide (edit. by Casida, J. E.) (Academic Press, 1973) (in the press).
3. Elliott, M., Bull. Wld Hlth Org., 44, 315 (1971).
4. Chen, Y.-L., and Casida, J. E., J. agric. Fd Chem., 17, 208 (1969).
5. Verschoyle, R. D., and Barnes, J. M., Pestic. Biochem. Physiol. 2, 308 (1972).