258 RADIATION BIOLOGY 



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Natl. Bur. Standards, 42: 209-217. 

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 Weston Electrical Instrument Corporation Technical data on Weston Photronic cell. 



Newark, N.J. 

 Williams, V. Z. (1948) Infrared instrumentation and techniques. Rev. Sci. Instr., 



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 Wormser, E. M. (1953) Properties of thermistor infrared detectors. J. Opt. Soc. 



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 Zworykin, V. K., and E. G. Ramberg (1949) Photoelectricity and its application. 



John Wiley & Sons, Inc., New York. 



Manuscript received by the editor June 25, 1953 



