@article{240766, recid = {240766}, author = {Long, H. Keith. and Farrar, Jerry W.}, title = {Report on the U.S. Geological Survey's evaluation program for standard reference samples distributed in April 1993 T-123 (trace constituents), T-125 (trace constituents), M-126 (major constituents), N-38 (nutrients), N-39 (nutrients), P-20 (low ionic strength), and Hg-16 (mercury) / [microform] :}, publisher = {U.S. Geological Survey ;}, address = {Golden, Colo. :}, pages = {iii, 149 p. :}, year = {1993}, note = {Chiefly tables.}, url = {http://library.usi.edu/record/240766}, }