References
Pilsbury, Henery A. 1948. Land Mollusca of North America, Vol 2, part 2, pg 921-923
Hubricht, Leslie. 1985. The Distributions of Native Land Mollusks of the Eastern United States, pg 8, 69
Burtch, John. 1962. How To Know the Eastern Land Snails, pg 46-47
Allaby, Michael. 1999. A Dictionary of Zoology
Miller, Barry B. 1970. The Sandhal Molluscan Fauna (Illinoian) From McPherson County, Kansas