| original |
Middle Ordovician |
|
Finland |
Uutela,A. Age and dispersal of sedimentary erratics on the coast of southwestern Finland. |
1989 |
| details |
Late Arenigian |
Early Caradocian |
USSR(Estonian SSR) |
Uutela,A. Age and dispersal of sedimentary erratics on the coast of southwestern Finland. |
1989 |
| details |
Nd |
|
Nd |
Servais,T. et al. A discussion and proposals concerning the Lower Paleozoic "Galeate" acritarch Plexus |
1995 |
| details |
Late Cambrian |
Early Ordovician |
Algeria |
Stricanne,L. et al. A statistical approach to classification of the Cambro-Ordovician galeate acritarch plexus |
2002 |