@misc{indiciaea578ba22ef2a,
  title = {GDA (Geologic Data Assistant), an ArcPad extension for geologic mapping: code, prerequisites, and instructions},
  author = {Evan E. Thoms and Ralph A. Haugerud},
  year = {2006},
  doi = {10.3133/ofr20061097},
  url = {https://pubs.usgs.gov/publication/ofr20061097},
  note = {Source identifier: ofr20061097}
}