References

Baker, F. 1939.  Field book of Illinois Land Snails.  Natural History of Survey Division. Illinois. 100.

Fitch, H. and Lokke, D.  1903.  The Molluscan Record of Succession on the University of Kansas Natural   History Reservation.  Kansas Academy of Science.  USA. 450.

Franzen and Leonard.  1943.  The University of Kansas Science Bulletin.  University of Kansas       Publications.  Lawrence, Kansas.  417-418.

Hubricht, L. 1985.  The distributions of the native land mollusks of the Eastern United Sates.  Field Mueseum of Natural History.  USA. 9.

Pilsbry, H.  1916. Manual of conchology, structural and systematic: Second Series.  Puslished by Author. Philadelphia. 28.

www.natureserve.org/explorer/servlet/NatureServe?searchName=Gastrocopta%20pentodon.  March 2011.