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Crick, F. H. C Banu'tt. L . Brenner, S. and R J W atts-Tobin, 1961. General 

 nature of the genetic code for proteins. Nature 192:1227-1232. 



Nirenberg, M. \N.. and J. H. Matthaei, 1961. The dependence of cell-free 

 protein synthesis in £. coli upon naturally occurring or synthetic polyribonu- 

 cleotides'. Proc. Natl. .\cad. Sci. Wash. 47:1588-1602. 



Henning, U. and C. Yanofsky, 1962. An alteration in the priman structure of a 

 protein predicted on the basis of genetic recombination data. Proc. Natl. Acad. 

 Sci. Wash. 48:183-190. 



Spever. J. F., Lengvel, P., Basilio C. and S. Ochoa. 1962. Synthetic polynu- 

 cleotides and the amino acid code. 1\ Pro?. Natl. Acad. Sci. Wash. 48:441- 

 448. 



