Cramer and Diez, 1976
From dinoflaj3
Cramer, F.H. and Diez, M.del C. R., 1976: Acritarchs from the La Vid Shales (Emsian to lower Couvinian) at Colle, Léon, Spain. Palaeontographica, Abteilung B, v.158, no.1-4, p.72-103, pl.1-7.