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Vree, T.B.; van der Kleijn, E.; Knop, H.J., Rapid determination of 4-hydroxybutyric acid (Gamma OH) and 2-propyl pentanoate (Depakine) in human plasma by means of gas-liquid chromatography, J. Chromatogr., 1976, 121, 1, 150-152, https://doi.org/10.1016/S0021-9673(00)82317-1 . [all data]