| details |
Ordovician |
|
USSR(Russian Platform) |
Umnova,N.I. et al. Acritarchs from the Yaroslavskoi series of the northern part of the Russian Platform |
1970 |
| original |
Middle Ordovician |
|
USSR(Yaroslav) |
Umnova,N.I. et al. Acritarchs from the Yaroslavskoi series of the northern part of the Russian Platform |
1970 |
| details |
Early Ordovician |
Middle Ordovician |
USSR(Russian Platform) |
Umnova,N.I. Ordovician and Silurian acritarchs of the Moscow Basin and Prebaltic |
1975 |
| details |
Middle Ordovician |
|
USSR(Yaroslav) |
Umnova,N.I. Ordovician and Silurian acritarchs of the Moscow Basin and Prebaltic |
1975 |