| details |
Late Wenlockian |
|
USSR(Kazakh SSR) |
Grishina,T.S. et al. Acritarchs from the Cyrtograptus Lundgreni zone of the Zaisan Folded system |
1981 |
| details |
Tremadocian |
|
France(Lot-et-Garonne) |
Baudelot,S. et al. Paleozoic basins hidden under the Aquitaine: Micropaleontological study of core collected during petroleum investigations. (In: Program of deep geology of France first phase of investigation-1983-1984) |
1984 |
| details |
Arenigian |
|
China(Shanghai) |
Hu,Y. Micropalaeoflora from the Early Ordovician in Gaoqiao Region of Shaanxi and its stratigraphic significance. |
1986 |
| details |
Early Ordovician |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |