@misc{indiciaef66550242c8d,
  title = {Aeromagnetic map of the Williamsburg quadrangle and part of the Shelburne Falls quadrangle, Franklin and Hampshire Counties, Massachusetts},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1969},
  doi = {10.3133/gp659},
  url = {https://pubs.usgs.gov/publication/gp659},
  note = {Source identifier: gp659}
}