Analysis of cocaine, benzoylecgonine, ecgonine methyl ester, and ecgonine by high-pressure liquid chromatography-API mass spectrometry and application to a short-term degradation study of cocaine in plasma
A. Klingmann et al., Analysis of cocaine, benzoylecgonine, ecgonine methyl ester, and ecgonine by high-pressure liquid chromatography-API mass spectrometry and application to a short-term degradation study of cocaine in plasma, J ANAL TOX, 25(6), 2001, pp. 425-430