@misc{indiciae152d6b4ef5d2,
  title = {Shaded relief map of the Caloris Planitia area of Mercury},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1979},
  doi = {10.3133/i1172},
  url = {https://pubs.usgs.gov/publication/i1172},
  note = {Source identifier: i1172}
}