@misc{indiciae2e378f94f58a,
  title = {A Fortran IV program for analytic continuation of VLF electromagnetic data},
  author = {Raymond D. Watts},
  year = {1975},
  doi = {10.3133/ofr75159},
  url = {https://pubs.usgs.gov/publication/ofr75159},
  note = {Source identifier: ofr75159}
}