| details |
Late Llandeilian |
Ashgillian |
USSR(Estonian SSR) |
Uutela,A. et al. Ordovician acritarchs from the Rapla borehole, Estonia |
1991 |
| original |
Middle Caradocian |
|
USSR(Estonian SSR) |
Uutela,A. et al. Ordovician acritarchs from the Rapla borehole, Estonia |
1991 |
| details |
Ottnangian |
Karpathian |
Hungary |
Nagy,E. A comprehensive study of Neogene sporomorphs in Hungary |
1992 |
| details |
Middle Ordovician |
Late Ordovician |
USSR(Estonian SSR) |
Sarjeant,W.A.S. et al. The Micrhystridium and Veryhachium Complexes (Acritarcha: Acanthomorphitae and Polygonomorphitae): A taxonomic reconsideration. |
1994 |