@misc{indiciaeaa1edf97221e,
  title = {Four models used for numerical simulation of a borehole radar antenna},
  author = {Karl J. Ellefsen and David L. Wright},
  year = {2003},
  doi = {10.3133/ofr03155},
  url = {https://pubs.usgs.gov/publication/ofr03155},
  note = {Source identifier: ofr03155}
}