@misc{indiciae31bebbe9a2d4,
  title = {Hadley-Apennine site shaded relief map},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1971},
  doi = {10.3133/ofr71304},
  url = {https://pubs.usgs.gov/publication/ofr71304},
  note = {Source identifier: ofr71304}
}