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Gilbert, M.T.; Brooks, C.J.W., Characterization of Diastereomeric and Enantiomeric Ephedrines by Gas Chromatography Combined with Electron Impact Mass Spectrometry and Isobutane Chemical Ionization Mass Spectrometry, Biomed. Mass Spectrom., 1977, 4, 4, 226-231, https://doi.org/10.1002/bms.1200040407 . [all data]