Barker G. M.: Gastropods on Land: Phylogeny, Diversity and Adaptive Morphology. in Barker G. M. (ed.): The biology of terrestrial molluscs. CABI Publishing, Oxon, UK, 2001, ISBN0-85199-318-4. 1-146, cited pages: 139 and 142.
Kantor Yu I., Vinarski M. V., Schileyko A. A. & Sysoev A. V.(published online on December 22, 2009). "Catalogue of the continental mollusks of Russia and adjacent territories". Version 2.3.
(in Russian) Zhiltsov S. S. & Schileyko A. A. (2002). "Morphology of reproductive system of Bielzia coerulans (Gastropoda, Pulmonata) and phylogenetic relations of the genus Bielzia". Ruthenica12: 73-79. abstract.