| original |
Middle Ordovician |
|
Sweden |
Kjellstrжm,G. Ordovician microplankton (baltisphaerids) from the Grotlingbo borehole No.1 in Gotland, Sweden. |
1971 |
| 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 |
Quaternary |
|
Sweden |
Tralau,H. Micropalaeontological analysis of Ordovician Flint artifacts from a Stone Age settlement at Ire, Gotland. (In: Studies in North European Archaeology. G.O.Janzon, editor) |
1974 |
| details |
Middle Ordovician |
|
Sweden |
Loeblich,A.R.,Jr. et al. Some Middle and Late Ordovician microphytoplankton from Central North America. |
1978 |
| details |
Llanvirnian |
|
United Kingdom |
Downie,C. Acritarchs in British stratigraphy |
1984 |
| details |
Middle Ordovician |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |