@misc{indiciae75b967337167,
  title = {Shaded relief map of the Chryse region of Mars},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1975},
  doi = {10.3133/i939},
  url = {https://pubs.usgs.gov/publication/i939},
  note = {Source identifier: i939}
}