@misc{indiciae4d54a51ccf6b,
  title = {Geologic map of the Robertson River Igneous Suite, Blue Ridge Province, northern and central Virginia},
  author = {R.P. Tollo and T.K. Lowe},
  year = {1994},
  doi = {10.3133/mf2229},
  url = {https://pubs.usgs.gov/publication/mf2229},
  note = {Source identifier: mf2229}
}