@misc{indiciae4de46cdca311,
  title = {Digital elevation models},
  author = {Atef A. Elassal and Vincent M. Caruso},
  year = {1983},
  doi = {10.3133/cir895b},
  url = {https://pubs.usgs.gov/publication/cir895B},
  note = {Source identifier: cir895B}
}