| original |
Late Llanvirnian |
|
E.Germany(Rostock) |
Burmann,G. Further organic microfossils from the Lower Ordovician. |
1970 |
| details |
Late Llanvirnian |
|
E.Germany |
Eisenack,A. et al. Catalog of fossil dinoflagellates, hystrichospheres and related microfossils. Acritarchs. |
1976 |
| details |
Late Llanvirnian |
|
Nd |
Diez,M.D.C.R. et al. Range chart of selected Lower Paleozoic acritarch Taxa. 2: Index to Parts 1 and 2. |
1977 |
| details |
Middle Arenigian |
Late Arenigian |
Bulgaria |
Kalvacheva,R.K. Palynological evidence for the Early-Ordovician (Arenigian) age of ophiolites in the Botevgran District (West Balkan Mountain) Bulgaria. |
1982 |
| details |
Late Arenigian |
|
Bulgaria |
Kalvacheva,R.K. Palynology and stratigraphy of the Diavase-Phyllitoid complex in the West Balkan Mountains. |
1982 |
| details |
Late Arenigian |
|
Bulgaria |
Kalvacheva,R.K. Acritarch evidence for Ordovician System in West Bulgaria |
1984 |
| details |
Late Llanvirnian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |