Sylvester-Bradley, P.C. (1949). The Ostracod genus Cypridea and the zones of the Upper and Middle Purbeckian. Proceedings of the Geologists' Association. 60(2):125-153.
The nomenclature ofthe genus Cypridea is clarified, and a valid genolectotype is selected. The shell characters of the genus are described. Stratigraphically significant species of the Upper and Middle Purbeck Beds are described, and their distribution incorporated in a revised zonal scheme.