@misc{indiciae1494309223ea,
  title = {A preliminary report on the stratigraphy of previously unreported Devonian ashfall localities in the Appalachian Basin},
  author = {John B. Roen},
  year = {1980},
  doi = {10.3133/ofr80505},
  url = {https://pubs.usgs.gov/publication/ofr80505},
  note = {Source identifier: ofr80505}
}