@misc{indiciae1168d2f0ce6c,
  title = {Geologic map of South America},
  author = {G. H. Goudarzi},
  year = {1977},
  doi = {10.3133/mf868a},
  url = {https://pubs.usgs.gov/publication/mf868A},
  note = {Source identifier: mf868A}
}