1. Birnstiel, M. L., Ann. Rev. Plant Physiol., 18, 48 (1967).
2. Wallace, H., and Birnstiel, M. L., Biochim. Biophys. Acta, 114, 296 (1966).
3. Brown, D. D., and Gurdon, J. B., Proc. US Nat. Acad. Sci., 51, 139 (1964).
4. Birnstiel, M. L., Wallace, H., Sirlin, J., and Fischberg, M., Nat. Cancer Inst. Mono., 23, 431 (1966).
5. Birnstiel, M. L., in Cell Differentiation, Ciba Foundation Symp. (edit. by de Reuck, A. V. S., and Knight, J.), 178 (J. and A. Churchill, London, 1967).