@misc{indiciae8989e634abff,
  title = {Maps showing the surficial geology of the Culebra shelf, Puerto Rico},
  author = {M. A. Hampton and M.E. Torresan and Juan L. Trias and D. W. Folger and F. L. Wong},
  year = {1997},
  doi = {10.3133/ofr97290},
  url = {https://pubs.usgs.gov/publication/ofr97290},
  note = {Source identifier: ofr97290}
}