| original |
Middle Siegenian |
Emsian |
Spain |
Cramer,F.H. Microplankton from three Palaeozoic formations in the Province of Leon, northwest Spain. |
1964 |
| details |
Late Siegenian |
Emsian |
Spain |
Cramer,F.H. Palynology of Silurian and Devonian rocks in northwest Spain. |
1966 |
| details |
Middle Siegenian |
Emsian |
Spain |
Eisenack,A. Critical remarks about Pterospermopsis |
1972 |
| details |
Middle Siegenian |
Emsian |
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |