(PDF document) Detection of endogenous ethanol and other compounds in the breath by gas chromatography with on-column concentration of sample.
Phillips M and Greenberg J
Analytical Biochemistry (1987); 163: 165-169
(PDF document) Detection of endogenous acetone in normal human breath.
Phillips M and Greenberg J
Journal of Chromatography. Biomedical Applications (1987); 422: 235-238