@misc{indiciae7500c3af4039,
  title = {Piedmont geology of the Spotsylvania Quadrangle, Spotsylvania County, Virginia},
  author = {Karen Wier and Louis Pavlides},
  year = {1985},
  doi = {10.3133/i1568},
  url = {https://pubs.usgs.gov/publication/i1568},
  note = {Source identifier: i1568}
}