@misc{indiciaeef3fe15f5ee0,
  title = {Map of the Berea and Murrysville sands of northeastern Ohio, western Pennsylvania, and northern-most West Virginia},
  author = {D. F. Demarest},
  year = {1946},
  doi = {10.3133/om49},
  url = {https://pubs.usgs.gov/publication/om49},
  note = {Source identifier: om49}
}