@misc{indiciaef9c018ed94f3,
  title = {Preliminary aeromagnetic map covering Greene County, Indiana},
  author = {John R. Henderson},
  year = {1949},
  doi = {10.3133/ofr4931},
  url = {https://pubs.usgs.gov/publication/ofr4931},
  note = {Source identifier: ofr4931}
}