@misc{indiciaeec1967081bd0,
  title = {Long-term biases in geomagnetic K and aa indices},
  author = {Jeffrey J. Love},
  year = {2011},
  doi = {10.5194/angeo-29-1365-2011},
  url = {https://pubs.usgs.gov/publication/70036380},
  note = {Source identifier: 70036380}
}