@misc{indiciae6218dc6c8e98,
  title = {Normapolles pollen from the Mississippi embayment},
  author = {Robert H. Tschudy},
  year = {1975},
  doi = {10.3133/pp865},
  url = {https://pubs.usgs.gov/publication/pp865},
  note = {Source identifier: pp865}
}