| original |
Late Cambrian |
Early Ordovician |
USSR(Pre-Baltic) |
Timofeev,B.V. Ancient flora of the Prebaltic Region and its stratigraphic significance |
1959 |
| details |
Tremadocian |
|
Poland |
Jagielska,L. Microspores of the older Palaeozoic from Bore-Hole Uszkowce 1. |
1962 |
| details |
Nd |
|
Nd |
Downie,C. et al. Bibliography and index of fossil dinoflagellates and acritarchs. |
1965 |
| details |
Ordovician |
|
Poland |
Jagielska,L. Flora of the Ordovician;Microflora |
1972 |
| details |
Tremadocian |
|
England(Shropshire) |
Rasul,S.M. et al. The stratigraphic distribution of Tremadoc acritarchs in the Shineton Shales succession, Shropshire, England. |
1974 |
| details |
Late Cambrian |
Early Ordovician |
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |