Davey, R.J. and Williams, G.L.,
1966a
IV. The genera Hystrichosphaera and Achomosphaera.
In: Davey, R.J., Downie, C., Sarjeant, W.A.S. and Williams, G.L., Studies on Mesozoic and Cainozoic dinoflagellate cysts; British Museum (Natural History) Geology, Bulletin, Supplement 3, p.28-52.