@misc{indiciae2a08572cdeee,
  title = {Shaded relief and surface markings of the Etana region of Ganymede},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1987},
  doi = {10.3133/i1810},
  url = {https://pubs.usgs.gov/publication/i1810},
  note = {Source identifier: i1810}
}