| original |
Arenigian |
|
E.Germany(Rostock) |
Burmann,G. Further organic microfossils from the Lower Ordovician. |
1970 |
| details |
Arenigian |
|
Canada(Newfoundland) |
Dean,W.T. et al. Lower Ordovician acritarchs and Trilobites from Bell Island, Eastern Newfoundland. |
1978 |
| details |
Early Paleozoic |
|
Nd |
Cramer,F.H. et al. Lower Paleozoic acritarchs. |
1979 |
| details |
Arenigian |
|
Canada(Newfoundland) |
Martin,F. Some aspects of Late Cambrian and Early Ordovician acritarchs. |
1982 |
| details |
Early Llanvirnian |
|
Czechoslovakia |
VavrdovЎ,M. Phytoplankton communities of Cambrian and Ordovician age of Central Bohemia |
1982 |
| details |
Late Arenigian |
Early Llanvirnian |
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |