RT Journal Article SR Electronic T1 Water quality effects of repeated annual poultry litter application JF Journal of Soil and Water Conservation FD Soil and Water Conservation Society SP 180A OP 180A DO 10.2489/jswc.64.6.180A VO 64 IS 6 A1 Daren Harmel YR 2009 UL http://www.jswconline.org/content/64/6/180A.abstract AB