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2. K. Lonsdale, Acta Cryst., Vol. 1, 1948, p. 12.
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4. L.S. Birks and A. B. Wing, NRL Report 4402, Naval Research Laboratory, Washington, D.C., 1954.
5. G. A. Jeffrey, G. E. Pringle, and J. R. Townsend, “Equipment for X-ray Crystal Structure Analysis,” Final Report from Scaife Radiation Laboratory, University of Pittsburgh, Pittsburgh, Pa., 1955.