TY  - RPRT
TI  - Report on the U.S. Geological Survey's evaluation program for standard reference samples distributed in October 1993 : T-127 (trace constituents), M-128 (major constituents), N-40 (nutrients), N-41 (nutrients), P-21 (low ionic strength), Hg-17 (mercury), AMW-3 (acid mine water), and WW-1 (whole water)
AU  - H.K. Long
AU  - J.W. Farrar
PY  - 1994
DO  - 10.3133/ofr9442
UR  - https://pubs.usgs.gov/publication/ofr9442
ID  - ofr9442
ER  -