| original |
Middle Cambrian |
|
USSR(Pre-Baltic) |
Timofeev,B.V. Ancient flora of the Prebaltic Region and its stratigraphic significance |
1959 |
| details |
Nd |
|
Nd |
Downie,C. et al. Bibliography and index of fossil dinoflagellates and acritarchs. |
1965 |
| details |
Early Ordovician |
|
England(Isle of Wight) |
Downie,C. et al. Microfossils from the Maxx Slate Series. |
1966 |
| details |
Arenigian |
Llanvirnian |
England(Durham) |
Lister,T.R. et al. Phytoplankton, (acritarchs), from a small Ordovician Inlier in Teesdale, (County Durham), England. |
1970 |
| details |
Late Cambrian |
|
Belgium |
Vanguestaine,M. The Late Cambrian age of the Upper RN2B from the Stavelot area. (In: Mikrofossilii Drevneishikh Otlozhenii. T.F.Vozzhennikova and T.B.Timofeev, editors) |
1973 |
| details |
Late Arenigian |
Early Llanvirnian |
England(Cumberland) |
Arthurton,R.S. et al. Ordovician and Silurian. (In: Geology of the Country around Penrith.) |
1981 |
| details |
Middle Cambrian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |