| Item Description: | "Chapter 6.4 of Section A, National Field Manual for the Collection of Water-Quality Data Book 9, Handbooks for Water-Resources Investigations."
"First release: April 1998, online as Techniques of Water-Resources Investigations (TWRI), book 9, chapter A6.4, version 1.0 revised: July 2003, online as TWRI 9-A6.4, version 1.2 revised: January 2006, online as TWRI 9-A6.4, version 1.3 revised: October 2008, online as TWRI 9-A6.4, version 2.0 revised: February 2021, online as Techniques and Methods, book 9, chapter A6"--Title page verso. |
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