@misc{indiciae655a006bcc72,
  title = {Geologic map of the Urbana quadrangle, Frederick and Montgomery Counties, Maryland},
  author = {Scott Southworth},
  year = {2000},
  doi = {10.3133/gq1768},
  url = {https://pubs.usgs.gov/publication/gq1768},
  note = {Source identifier: gq1768}
}