RT Journal Article SR Electronic T1 A sinkhole filter for protection of karst groundwater JF Journal of Soil and Water Conservation FD Soil and Water Conservation Society SP 25A OP 25A DO 10.2489/jswc.63.1.25A VO 63 IS 1 A1 Boyer, Douglas G. YR 2008 UL http://www.jswconline.org/content/63/1/25A.abstract AB