| details |
Late Arenigian |
|
England(Cumberland) |
Arthurton,R.S. et al. Ordovician and Silurian. (In: Geology of the Country around Penrith.) |
1981 |
| details |
Late Cambrian |
Ordovician |
Romania |
Paraschiv,D. et al. The present Stage of Pre-Jurassic deposits knowledge in South Dobrogea |
1983 |
| details |
Late Cambrian |
Early Ordovician |
Romania |
Paraschiv,D. et al. On the Pre-Neogene Formations in the North-Dobrogean Promontory |
1983 |
| details |
Early Ordovician |
|
USSR(Pre-Baltic) |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |