| details |
Caradocian |
Ludlovian |
USSR(Russian Platform) |
Umnova,N.I. Silurian and Ordovician acritarch assemblages from the northern and western parts of the Russian Platform. |
1974 |
| details |
Caradocian |
Ludlovian |
USSR(Pre-Baltic) |
Umnova,N.I. Silurian and Ordovician acritarch assemblages from the northern and western parts of the Russian Platform. |
1974 |
| details |
Ludlovian |
|
USSR(Russian Platform) |
Umnova,N.I. Ordovician and Silurian acritarchs of the Moscow Basin and Prebaltic |
1975 |
| details |
Proterozoic |
Middle Ordovician |
USSR(Pre-Baltic) |
Umnova,N.I. Ordovician and Silurian acritarchs of the Moscow Basin and Prebaltic |
1975 |