@misc{indiciae42aa2aca4e66,
  title = {Magnetic signals from the core of the earth and secular variation},
  author = {L.R. Alldredge},
  year = {2012},
  doi = {10.1029/jb086ib09p07957},
  url = {https://pubs.usgs.gov/publication/70011867},
  note = {Source identifier: 70011867}
}