http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Trends in nutrient concentration and load for streams in the Mississippi River Basin, 1974-94
1 online resource (iv, 62 pages) : illustrations, maps here.
by D.L. Lurry and D.D. Dunn ; prepared in cooperation with the U.S. Environmental Protection Agency, Gulf of Mexico Program, Nutrient Enrichment Issue Committee.
Includes bibliographical references (pages 21-22).
Water-resources investigations report ; 97-4223