Sarjeant, 1981
From dinoflaj3
Sarjeant, W.A.S., 1981: A restudy of some dinoflagellate cyst holotypes in the University of Kiel Collections. II. The Eocene holotypes of Barbara Klumpp (1953); with a revision of the genus Cordosphaeridium Eisenack, 1963. Meyniana, v.33, p.97-132, pl.1-6.