1. Adanson, M., 1763. Familles des Plantes 2. Vincent, Paris, p. 76.
2. Fossil plants of the Tertiary Beaverhead Basins in southwestern Montana;Becker H.F.;Palaeontographica Abteilung B,1969
3. Uppermost Cretaceous and Paleocene floras of western Alberta;Bell W.A.;Geological Survey of Canada, Bulletin,1949
4. The flora of the Matawan Formation (Crosswicks Clays);Berry E.W.;New York Botanical Garden, Bulletin,1903
5. Geologic history indicated by the fossiliferous deposits of the Wilcox Group (Eocene) at Meridian, Mississippi;Berry E.W.;Washington Geological Survey,1917