| original |
Middle Ordovician |
|
Sweden |
Kjellstrжm,G. Ordovician microplankton (baltisphaerids) from the Grotlingbo borehole No.1 in Gotland, Sweden. |
1971 |
| details |
Middle Ordovician |
|
Sweden |
Kjellstrжm,G. Lower Viruan microplankton from a Boring in Oland, Sweden |
1972 |
| details |
Ordovician |
|
Sweden |
Eisenack,A. et al. Catalog of fossil dinoflagellates, hystrichospheres and related microfossils. Acritarchs. |
1973 |
| details |
Llanvirnian |
Llandeilian |
Nd |
Diez,M.D.C.R. et al. Range chart of selected Lower Paleozoic acritarch Taxa. |
1974 |
| details |
Middle Ordovician |
|
Finland |
Tynni,R. Ordovician hystrichospheres and chitinozoans in limestone from the Bothnian Sea. |
1975 |
| details |
Middle Ordovician |
|
Sweden |
Kjellstrжm,G. Lower Viruan Middle Ordovician microplankton from the Ekon borehole No.1 in Ostergotland, Sweden. |
1976 |
| details |
Middle Ordovician |
|
Sweden |
Loeblich,A.R.,Jr. et al. Some Middle and Late Ordovician microphytoplankton from Central North America. |
1978 |
| details |
Middle Ordovician |
|
USSR(Estonian SSR) |
Bockelie,T.G. et al. Middle Ordovician acritarchs from the Island of Odinsholm, Estonia. |
1979 |
| details |
Early Paleozoic |
|
Nd |
Cramer,F.H. et al. Lower Paleozoic acritarchs. |
1979 |
| details |
Late Champlainian |
Early Cincinnatian |
Canada(Quebec) |
Martin,F. Ordovician chitinozoa and acritarchs of the Saint-Laurent Platform, (Quebec and Southeast Ontario). |
1983 |
| details |
Middle Ordovician |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |