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Atomic Definition of Primary Standards

Naturevolume 166pages167168 (1950) | Download Citation


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    9th General Conference of Weights and Measures, 1948, Sèvres, France.

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    Lyons, H., “Microwave Spectroscopic Frequency and Time Standards”, Elec. Eng., 68, 251 (1949). “The Atomic Clock, An Atomic Standard of Frequency and Time”, N.B.S. Tech. News Bull., 33, 17 (1949).

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    Thomas, H. A., Driscoll, R. L., and Hipple, J. A., Phys. Rev., 75, 902 (1949).

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    Michelson, A. A., and Morley, E. W., Amer. J. Sci., 38, 181 (1889).

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    Perard, A., and Terrien, J., C.R. Acad. Sci., Paris, 228, 964 (1949).

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    Essen, L., Nature, 159, 611 (1947). Essen, L., and Gordon Smith, A. C., Proc. Roy. Soc., A, 194, 348 (1948).

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  1. National Bureau of Standards, Washington, D.C.

    • DR. R. D. HUNTOON
    •  & DR. U. FANO


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