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Results of the U.S. Geological Survey's analytical evaluation program for standard reference samples : T-151(trace constituents), M-144 (major constituents), N-55 (nutrient constituents), N-56 (nutrient constituents), P-29 (low ionic strength constituents), GWT-2 (ground-water trace constituents), GWM-2 (ground-water major constituents), AMW-4 (acid mine water constituents), and Hg-25 (mercury) distributed in September 1997

J.W. Farrar
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J.W. Farrar. 1998. Results of the U.S. Geological Survey's analytical evaluation program for standard reference samples : T-151(trace constituents), M-144 (major constituents), N-55 (nutrient constituents), N-56 (nutrient constituents), P-29 (low ionic strength constituents), GWT-2 (ground-water trace constituents), GWM-2 (ground-water major constituents), AMW-4 (acid mine water constituents), and Hg-25 (mercury) distributed in September 1997. https://doi.org/10.3133/ofr9852

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