@misc{indiciaea0b806f61521,
  title = {Aeromagnetic map of part of the Haverhill quadrangle, Essex County, Massachusetts, and Rockingham County, New Hampshire},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1970},
  doi = {10.3133/gp713},
  url = {https://pubs.usgs.gov/publication/gp713},
  note = {Source identifier: gp713}
}