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3U.S.EPA.,EPA Requirements for Quality Assurance Project Plans,QA/R-5,Office of Environmental Information,Washington,March 2001.
4U.S.EPA.,Guidance for Quality Assurance Project Plans,QA/G-5,Office of Environmental Information,Washington,December 2002.
5U.S.EPA.,Guidance for Preparing Standard Operating Procedures(SOPs),QA/G-6,Office of Environmental Information,Washington,April 2007.
6U.S.EPA.,Guidance on Environmental Data Verification and Data Validation,QA/G-8,Office of Environmental Information,Washington,November 2002.
7U.S.EPA.,Guidance on Technical Audits and Related Assessments for Environmental Data Operations,QA/G-7,Office of Environmental Information,Washington,January 2000.
8U.S.EPA.,Data Quality Assessment:A Reviewer's Guide,QA/G-9R,Office of Environ-mental Information,Washington,February 2006.
9U.S.EPA.,Data Quality Assessment:Statistical Methods for Practitioners,QA/G-9S,Office of Environmental Information,Washington,February 2006.