| original |
Early Llandoverian |
|
Belgium |
Martin,F. The Upper Ordovician and Lower Silurian at Deerlijk (Belgium) |
1973 |
| details |
Early Tremadocian |
|
Belgium |
Martin,F. Cambrian-Ordovician acritarchs of the Massif du Brabant, Belgium. |
1975 |
| 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 |
Nd |
|
Nd |
Albani,R. Ordovician, (Arenigian) acritarchs from the Solanas Sandstone Formation, Central Sardinia, Italy. |
1989 |
| details |
Early Llandoverian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |