@misc{indiciae6b8e7f22c010,
  title = {CONTOUR; a modification of G.I. Evenden's general purpose contouring program},
  author = {R. H. Godson and M. W. Webring},
  year = {1982},
  doi = {10.3133/ofr82797},
  url = {https://pubs.usgs.gov/publication/ofr82797},
  note = {Source identifier: ofr82797}
}