@misc{indiciae853368870900,
  title = {Preliminary geologic map of the Schickard Quadrangle of the Moon},
  author = {N.V. Karlstrom},
  year = {1971},
  doi = {10.3133/ofr71169},
  url = {https://pubs.usgs.gov/publication/ofr71169},
  note = {Source identifier: ofr71169}
}