@misc{indiciae261ad949a1fe,
  title = {International Geomagnetic Reference Field 1980: charts and grid values, IAGA Bulletin No. 47},
  author = {Eugene B. Fabiano and N.W. Peddie and D.R. Barraclough and A.K. Zunde},
  year = {1982},
  doi = {10.3133/ofr82377},
  url = {https://pubs.usgs.gov/publication/ofr82377},
  note = {Source identifier: ofr82377}
}