Williams and Downie, 1966b
From dinoflaj2
Williams, G.L. and Downie, C., 1966b: Wetzeliella from the London Clay. 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.182-198.