Sarjeant et al., 1987
From dinoflaj3
Sarjeant, W.A.S., Lacalli, T. and Gaines, G., 1987: The cysts and skeletal elements of dinoflagellates: speculations on the ecological causes for their morphology and development. Micropaleontology, v.33, no.1, p.1-36, pl.1-3.