| details |
Llanvirnian |
Ludlovian |
USSR(Russian Platform) |
Umnova,N.I. Silurian and Ordovician acritarch assemblages from the northern and western parts of the Russian Platform. |
1974 |
| details |
Llanvirnian |
Ludlovian |
USSR(Pre-Baltic) |
Umnova,N.I. Silurian and Ordovician acritarch assemblages from the northern and western parts of the Russian Platform. |
1974 |
| details |
Ordovician |
|
USSR(Russian Platform) |
Umnova,N.I. Ordovician and Silurian acritarchs of the Moscow Basin and Prebaltic |
1975 |
| details |
Ordovician |
|
USSR(Yaroslav) |
Umnova,N.I. Ordovician and Silurian acritarchs of the Moscow Basin and Prebaltic |
1975 |
| details |
Silurian |
|
USSR(Buryat ASSR) |
Butov,Y.P. Some problems of Pre-Mesozoic stratigraphy of Savan-Baikal Mountain Region. 2. New data on the age of Pre-Mesozoic deposits. |
1986 |