| details |
Nd |
|
North Dakota |
Hickey,L.J. Stratigraphy and paleobotany of the Golden Valley Formation (Early Tertiary) of Western North Dakota. |
1977 |
| details |
Ypresian |
|
Worldwide |
Kovach,W.L. et al. Worldwide stratigraphic occurrences of Mesozoic and Tertiary megaspores. |
1989 |
| details |
Early Eocene |
|
North Dakota |
Batten,D.J. et al. Catalog of Mesozoic and Tertiary megaspores |
1990 |
| details |
Nd |
|
Nd |
Collinson,M.E. Diversification of modern Heterosporous Pteridophytes. (In: Pollen and Spores, Patterns of Diversification. S.Blackmore and S.H.Barnes, editors) |
1991 |
| details |
Cretaceous |
|
USA |
Balme,B.E. Fossil in situ, spores and pollen grains: An annotated catalogue. |
1995 |