@misc{indiciae81e575bf3df4,
  title = {Geologic Map of the Frederick 30' x 60' Quadrangle, Maryland, Virginia, and West Virginia},
  author = {Scott Southworth and David K. Brezinski and Avery Drake and William C. Burton and Randall C. Orndorff and Albert J. Froelich and James E. Reddy and Danielle Denenny and David L. Daniels},
  year = {2007},
  doi = {10.3133/sim2889},
  url = {https://pubs.usgs.gov/publication/sim2889},
  note = {Source identifier: sim2889}
}