@misc{indiciaee097725da367,
  title = {Phosphate rock in Colombia - a preliminary report, with a section on the phosphate occurrence at Turmeque},
  author = {James Bachelder Cathcart and Francisco Zambrano O. and Pedro Mojica G.},
  year = {1967},
  doi = {10.3133/ofr6743},
  url = {https://pubs.usgs.gov/publication/ofr6743},
  note = {Source identifier: ofr6743}
}