Paez-Reyes and Head, 2013
From dinoflaj3
Paez-Reyes, M and Head, M.J., 2013: The Cenozoic gonyaulacacean dinoflagellate genera Operculodinium Wall, 1967 and Protoceratium Bergh, 1881 and their phylogenetic relationships. Journal of Paleontology, v.87, no.5, p.786-803.