@misc{indiciaed20f94844b12,
  title = {Mineral deposits of Central America, with a section on manganese deposits of Panama},
  author = {Ralph Jackson Roberts and Earl Montgomery Irving and F. S. Simons},
  year = {1957},
  doi = {10.3133/b1034},
  url = {https://pubs.usgs.gov/publication/b1034},
  note = {Source identifier: b1034}
}