Weinkauf et al., 2013
From dinoflaj3
Weinkauf, M.F.G., Keupp, H. and Mutterlose, J., 2013: Calcareous dinoflagellates from the Late Hauterivian (Early Cretaceous) of Frielingen, Germany. Documenta naturae, v.192, no.3, p.241-271.