TY - RPRT TI - Evaluation of Nitrate Concentrations and Sources in the Elk Creek Watershed, Southwestern Ohio, 2003-2004 AU - Thomas L. Schumann AU - Bruce A. Pletsch PY - 2006 DO - 10.3133/sir20065223 UR - https://pubs.usgs.gov/publication/sir20065223 ID - sir20065223 ER -