@misc{indiciaea77672d50f92,
  title = {Digital geologic map and database of the Chesapeake and Ohio Canal National Historical Park and Potomac River corridor, District of Columbia, Virginia, Maryland, and West Virginia},
  author = {C. Scott Southworth and David K. Brezinski and Randall C. Orndorff and Peter G. Chirico and Kerry M. Lagueux},
  year = {2001},
  doi = {10.3133/ofr01188a},
  url = {https://pubs.usgs.gov/publication/ofr01188A},
  note = {Source identifier: ofr01188A}
}