@misc{indiciaed732990ade48,
  title = {Forward-modeling computer program for the inductive electromagnetic ground-conductivity method; EM34.FOR},
  author = {Deborah G. Grantham and Karl Ellefsen and F.P. Haeni},
  year = {1987},
  doi = {10.3133/ofr87213a},
  url = {https://pubs.usgs.gov/publication/ofr87213A},
  note = {Source identifier: ofr87213A}
}