@misc{indiciaea52c2b0d5173,
  title = {Aeromagnetic map of part of the Unionville quadrangle, Chester County, Pennsylvania},
  author = {Randolph Wilson Bromery and G. L. Zandle},
  year = {1960},
  doi = {10.3133/gp226},
  url = {https://pubs.usgs.gov/publication/gp226},
  note = {Source identifier: gp226}
}