1. Aleson E, Redell J, Schuster W, Thomas G (2014) Management plan for Horseshoe Bay Cave. https://map.co.door.wi.us/parks/Horseshoe%20Bay%20Cave%20Management%20Plan%20(Approved%20June%2024,%202014).pdf
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3. Appleton Post-Crescent (2017) Greenville karst obliterated, https://www.postcrescent.com/story/news/local/2017/04/07/greenville-pulls-nasty-obliterating-karst/99682980/. Accessed 25 Feb 2017
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