1. Analysis of Sinkhole Susceptibility and Karst Distribution in the Northern Shenandoah Valley, Virginia: Implications for Low Impact Development (LID) Site Suitability Models;Hyland,2006
2. Karst Geomorphology and Hydrogeology;Ford,2007
3. Encyclopedia of Caves and Karst Science;Gunn,2004
4. http://resaweb.dlr.de/fileadmin/resa/documents/berichte/2012/RESA_02_2012_0621.pdf