@misc{indiciaeef5abc1b8b7b,
  title = {Aeromagnetic map of the Spencer Lake quadrangle, Franklin and Somerset Counties, Maine},
  author = {R. W. Bromery and Harry Soday},
  year = {1963},
  doi = {10.3133/gp331},
  url = {https://pubs.usgs.gov/publication/gp331},
  note = {Source identifier: gp331}
}