Biscutum testudinarium Black in Black & Barnes, 1959
Bidiscus Bukry, 1969
Cenorbiculus Burns, 1976
Black, M. & Barnes, B., (1959): The structure of Coccoliths from the English Chalk. - Geological Magazine. 96(5): 321-328.
Bukry, D., (1969): Upper Cretaceous coccoliths from Texas and Europe. - University of Kansas Paleontological Contributions, Articles. 51 (Protista 2): 1-79.
Burns, D. A., (1976): Nannofossils from the Lower and Upper Cretaceous deposits, Nettleton, Lincolnshire, England. - Revista Española de Micropaleontología. 8(2): 279-300.