TY  - RPRT
TI  - Report on the U.S. Geological Survey's evaluation program for standard reference samples distributed in April 1996 : T-139 (trace constituents), T-141 (trace constituents), M-138 (trace constituents), N-49 (nutrient constituents), N-50 (nutrient constituents), P-26 (low ionic strength constituents) and Hg-22 (Mercury)
AU  - J.W. Farrar
AU  - H.K. Long
PY  - 1996
DO  - 10.3133/ofr96436
UR  - https://pubs.usgs.gov/publication/ofr96436
ID  - ofr96436
ER  -