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3. R. A. Bonham and M. Fink, “High Energy Electron Scattering”, ( Van Nostrand Reinhold Co., New York, 1974 ).
4. B. K. Jap and R. M. Glaeser, Acta Cryst. A34, 94 (1978).
5. In a typical electron diffraction experiment with 40 keV electrons we have X = 0.05A,emax = 20°, sin(emax)/X = 3.74A-1 and o S = K = 43.61–1. Some measurements have been made to S = K = 701–1.