Wicander and Wood, 1981
From dinoflaj3
Wicander, E.R. and Wood, G.D., 1981: Systematics and biostratigraphy of the organic-walled microphytoplankton from the Middle Devonian (Givetian) Silica Formation, Ohio, U.S.A. American Association of Stratigraphic Palynologists, Contributions Series, no.8, p.1-137, pl.1-17.