198 RADIOISOTOPES IN BIOLOGY AND AGRICULTURE 



5. "Methods of Analysis of the Association of Official Agricultural Chemists," 6th 

 ed., Association of Official Agricultural Chemists, Washington, D.C., 1945. 



6. Calvin, Melvin, Charles Heidelberger, James C. Reid, Bert M. Tolbert, and 

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7. Friedlander, Gerhart, and Joseph W. Kennedy: "Introduction to Radiochemis- 

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8. Cook, G. B., and J. F. Duncan: "Modern Radiochemical Practice," Oxford 

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9. Siri, William E. : "Isotopic Tracers and Nuclear Radiations," McGraw-Hill Book 

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10. Korff, Serge A.: "Electron and Nuclear Counters," D. Van Nostrand Company, 

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11. Bleuler, Ernst, and George J. Goldsmith: "Experimental Nucleonics," Rinehart & 

 Company, Inc., New York, 1952. 



12. "Nucleonics Annual Buyers' Guide," McGraw-Hill Publishing Company, Inc., 

 New York. 



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15. Howarth, Frank: Tissue Suspensions for Estimations of Radioactivity, Nature, 

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16. Tabern, D. L. : Personal communication. 



17. Middleton, G., and R. E. Stuckey: The Preparation of Biological Material for the 

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18. Cotton, Robert H.: Determination of Nitrogen, Phosphorus, and Potassium in 

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19. Kelley, Omer J., Albert S. Hunter, and Athan J. Sterges: Determination of 

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20. Wolf, Benjamin: Rapid Photometric Determination of Total Nitrogen, Phos- 

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21. Parks, R. Q., S. L. Hood, Charles Hurwitz, and G. H. Ellis: Quantitative Chemi- 

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22. Lindner, R. C, and C. P. Harley: A Rapid Method for the Determination of 

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23. Van Slyke, Donald D., and Jordi Folch: Manometric Carbon Determination, 

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24. Van Slyke, Donald D., John Plazin, and James R. Weisiger: Reagents for the 

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25. Van Slyke, Donald D., Robert Steele, and John Plazin: Determination of Total 

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26. Claycomb, Cecil K., Tyra T. Hutchens, and John T. Van Bruggen: Techniques in 

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