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Periodical. Cowie, Dean B., Sol Spiegelman, Richard B. Roberts, and J. D. Duerksen. "Ribosome-Bound [Beta]-Galactosidase." Proceedings of the National Academy of Sciences of the United States of America 47, 1 (January 1961): 114-122. Article. 9 Images.. Proceedings of the National Academy of Sciences of the United States of America