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Hurly JJ, Moldover MR.Hurly JJ, et al.J Res Natl Inst Stand Technol. 2000 Oct 1;105(5):667-88. doi: 10.6028/jres.105.054. Print 2000 Sep-Oct.J Res Natl Inst Stand Technol. 2000.PMID: 27551630Free PMC article.