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Periodical. Bessman, Maurice J., I. Robert Lehman, Julius Adler, Steven B. Zimmerman, Ernest S. Simms, and Arthur Kornberg. "Enzymatic Synthesis of Deoxyribonucleic Acid. III. The Incorporation of Pyrimidine and Purine Analogues into Deoxyribonucleic Acid." Proceedings of the National Academy of Sciences of the United States of America 44, 7 (15 July 1958): 633-640. Article. 8 Images.. Proceedings of the National Academy of Sciences of the United States of America