Head, 1992
From dinoflaj2
Head, M.J., 1992: Zygospores of the Zygnemataceae (Division Chlorophyta) and other freshwater algal spores from the uppermost Pliocene St. Erth Beds of Cornwall, southwestern England. Micropaleontology, v.38, no.3, p.237-260, pl.1-4.
