@misc{indiciae06bef22a4c6e,
  title = {Geologic map of the Zorzor Quadrangle, Liberia},
  author = {J. F. Seitz},
  year = {1977},
  doi = {10.3133/i773d},
  url = {https://pubs.usgs.gov/publication/i773D},
  note = {Source identifier: i773D}
}