@misc{indiciaebdc305f72043,
  title = {An interpolation program for Texas Instruments 58/59 series programmable calculators with application to contour maps},
  author = {Steven M. Condon},
  year = {1980},
  doi = {10.3133/ofr80939},
  url = {https://pubs.usgs.gov/publication/ofr80939},
  note = {Source identifier: ofr80939}
}