@misc{indiciae81393f2d0953,
  title = {Preliminary geologic map of the Beltsville quadrangle, Prince Georges, Montgomery, and Howard Counties, Maryland},
  author = {C. F. Withington and A.J. Froelich},
  year = {1974},
  doi = {10.3133/mf582},
  url = {https://pubs.usgs.gov/publication/mf582},
  note = {Source identifier: mf582}
}