37. J. Papaconstantinou, P. V. Koehn and J, A. 

 Stewart. Abst. 148th Meeting of ACS, p. 39C 

 (1964). 



38. J. Papaconstantinou, J. A. Stewart and P. V. 

 Koehn. Biochim. Biophys. Acta, in press. 



39. C. Levinthal, A. Kenyon, and A. Higa. 

 Proc. Natl. Acad. Set. U.S. 48, 1631(1962). 



40. M. R. Pollock, Biochim, Biophys. Acta 76, 

 80 (1963). 



41. L. D. Garren, R. R. Howell, G. M. Tomkins 

 and R. M. Crocco. Proc. Natl. Acad. Set, 

 U.S. 52, 1121 (1964). 



42. J. D. Mandell and A. D. Hershey. Anal. 

 Biochem. l, 66 (1960). 



43. N. Sueoka, and T. Cheng. J. Mol. Biol. 4, 

 161 (1962). 



44. J, E. M. Midgley. Biochem. Biophys. Acta 

 61, 513 (1962). 



45. J. Papaconstantinou, Science, in press. 



67 



