J.  Alder and Hancock, A., ?Additions to the Mollusca of Northumberland and Durham?, Transactions of the Tyneside Field Club, vol. 1, pp. 195-207, 1848.

E.  Forbes and Hanley, S. C. T., A History of the British Molluscs and their shells, vol. 1. London: , 1848, p. 54.