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2. Crick, F. H., in Cellular Biology, Nucleic Acids and Viruses, special publications, New York Acad. Sci., 5, 173 (1957).
3. Rich, A., in The Chemical Basis of Heredity, edit. by McElroy, W. D., and Glass, B., 557 (Johns Hopkins Press, 1957).
4. Watson, J. D., ibid., 52.
5. Smith, J. D., and Markham, R., Nature, 170, 120 (1952).