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Paxon TL, Powell PR, Lee HG, Han KA, Ewing AG.Paxon TL, et al. Among authors: ewing ag.Anal Chem. 2005 Aug 15;77(16):5349-55. doi: 10.1021/ac050474m.Anal Chem. 2005.PMID: 16097779Free PMC article.