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- Winkler titration (See, for example http://web.colby.edu/colbyatsea/2011/02/11/winkler-titrations-measuring-dissolved-oxygen/ or http://water.usgs.gov/owq/FieldManual/Chapter6/Archive/Section6.2.pdf)
- Air-saturated water (See, for example http://water.usgs.gov/owq/FieldManual/Chapter6/Archive/Section6.2.pdf)
- Water-saturated air (Hanna Instruments's video of calibration: http://www.youtube.com/watch?v=sxI_PS7b8XI) [6]
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