| details |
Late Llandoverian |
Early Gedinnian |
Spain |
Cramer,F.H. Chitinozoans of a composite section of Upper Lland overian to Basal Lower Gedinnian sediments in Nort Hern Leon, Spain. a Prelimnary report. |
1966 |
| details |
Middle Gothlandian |
Late Gothlandian |
Spain |
Cramer,F.H. et al. Taxonomic considerations on the acritarchs of the Middle and Upper Silurian of northern Spain. |
1968 |
| details |
Late Llandoverian |
Early Gedinnian |
Spain |
Cramer,F.H. Consideration on the palynology and Silurian paleolatitudes based on microplankton of the Cantabrian Mountains of the Northwest of Spain. |
1969 |