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3. I. S. Boyce, C. G. Clayton, and D. Page, “Some Considerations Relating to the Accuracy of Measuring the Ash Content of Coal by X-Ray Backscattering,” Nucl. Tech. Miner. Resour., Proc. Int. Symp. 1977, IAEA: Vienna, Austria, 135–65 (1978).
4. R. C. Reynolds, Jr., “Matrix Corrections in Trace Element Analysis by X-Ray Fluorescence: Estimation of the Mass Absorption Co-efficient by Compton Scattering,” Amer. Miner. 48: 1133–43 (1964).
5. R. C. Reynolds, Jr., “Estimation of Mass Absorption Coefficients by Compton Scattering: Improvements and Extensions of the Method,” Amer. Miner. 52: 1493–1502 (1964).