TY  - RPRT
TI  - Report on the U.S. Geological Survey's evaluation program for standard reference samples distributed in October 1992, T-121 (trace constituents), M-124 (major constituents), N-36 (nutrients), N-37 (nutrients), P-19 (low ionic strength) and Hg-15 (mercury)
AU  - H.K. Long
AU  - J.W. Farrar
PY  - 1993
DO  - 10.3133/ofr9332
UR  - https://pubs.usgs.gov/publication/ofr9332
ID  - ofr9332
ER  -