@misc{indiciae4977b40bc17f,
  title = {Aeromagnetic map of the Shrewsbury quadrangle, Worcester County, Massachusetts},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1969},
  doi = {10.3133/gp672},
  url = {https://pubs.usgs.gov/publication/gp672},
  note = {Source identifier: gp672}
}