@misc{indiciae239f4dc01aa1,
  title = {Index map of 1:500,000-scale geologic and geographic maps of the Arabian Peninsula},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1980},
  doi = {10.3133/ofr81474},
  url = {https://pubs.usgs.gov/publication/ofr81474},
  note = {Source identifier: ofr81474}
}