@misc{indiciaefcf154cb9b06,
  title = {Geographic map of the south central Rub Al Khali quadrangle, Kingdom of Saudi Arabia},
  author = {Leon F. Ramirez and E.L. Elberg and H.H. Helley},
  year = {1962},
  doi = {10.3133/i219b},
  url = {https://pubs.usgs.gov/publication/i219B},
  note = {Source identifier: i219B}
}