@misc{indiciaeb74d72a423e4,
  title = {Upper Paleozoic floral zones and floral provinces of the United States, with a glossary of stratigraphic terms},
  author = {Charles Brian Read and Sergius H. Mamay and Grace C. Keroher},
  year = {1964},
  doi = {10.3133/pp454k},
  url = {https://pubs.usgs.gov/publication/pp454K},
  note = {Source identifier: pp454K}
}