Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : determination of organophosphate pesticides in bottom sediment by gas chromatography with flame photometric detection
Also available via Internet from the NWQL web site. Address as of 2/23/04: http://nwql.usgs.gov/Public/pubs/WRIR02-4222/WRIR02-4222.pdf; current access is available via PURL.
Microfiche. [Washington, D.C.] : Supt. of Docs., U.S. G.P.O., 2004 1 microfiche : negative.