@misc{indiciae7c000c406175,
  title = {List of references on the geology of Puerto Rico, 1866-1967},
  author = {Marjorie Hooker},
  year = {1968},
  doi = {10.3133/ofr68139},
  url = {https://pubs.usgs.gov/publication/ofr68139},
  note = {Source identifier: ofr68139}
}