@misc{indiciaec7c121afb1b2,
  title = {Geology of the eastern Piedmont in Virginia},
  author = {J. Wright Horton and Brent E. Owens and Paul C. Hackley and William C. Burton and Paul E. Sacks and James P. Hibbard},
  year = {2016},
  url = {https://pubs.usgs.gov/publication/70179666},
  note = {Source identifier: 70179666}
}