Phosphorus concentrations in stream-water and reference samples [electronic resource] : an assessment of laboratory comparability / by Michael R. McHale and Dennis McChesney ; prepared in cooperation with the U.S. Environmental Protection Agency.
Mode of access: Internet via the USGS web site. Address as of 02/27/08: http://pubs.usgs.gov/of/2007/1267/OFR2007-1267.pdf; current access available via PURL.
Note
Title from PDF title screen (viewed on Jan. 4, 2008).