User's guide for the gas chromatography automation system /

Mode of access: Internet.

Performance tests for the evaluation of computerized gas chromatography/mass spectrometry equipment and laboratories /

"April 1980"--Cover.

Method of analysis and quality-assurance practices for determination of pesticides in water by solid-phase extraction and capillary-column gas chromatography/mass spectrometry at the U.S. Geological Survey California District Organic Chemistry Laboratory, 1996-99 /

Mode of access: Internet.