@misc{indiciae787edf322adc,
  title = {Active tensor magnetic gradiometer system final report for Project MM–1514},
  author = {David V. Smith and Jeffrey D. Phillips and S. Raymond Hutton},
  year = {2014},
  doi = {10.3133/ofr20131228},
  url = {https://pubs.usgs.gov/publication/ofr20131228},
  note = {Source identifier: ofr20131228}
}