| details |
Late Cretaceous |
Paleocene |
Montana |
Norton,N.J. Palynology of the Upper Cretaceous and Lower Tertiary in the type locality of the Hell Creek Formation |
1965 |
| original |
Late Cretaceous |
Early Paleocene |
Montana |
Norton,N.J. et al. Palynology of the Upper Cretaceous and Lower Tertiary in the type locality of the Hell Creek Formation, Montana, USA. |
1969 |
| details |
Maastrichtian |
Paleocene |
North America |
Lupia,R. Discordant morphological disparity and taxonomic diversity during the Cretaceous angiosperm radiation: North American pollen record. |
1999 |