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Periodical. Spiegelman, Sol, I. Haruna, I. B. Holland, G. Beaudreau, and D. R. Mills. "The Synthesis of a Self-Propagating and Infectious Nucleic Acid with a Purified Enzyme." Proceedings of the National Academy of Sciences of the United States of America 54, 3 (September 1965): 919-927. Article. 9 Images.. Proceedings of the National Academy of Sciences of the United States of America