@misc{indiciaec1d2d5e88f6e,
  title = {Digitizing zone maps, using modified LARSYS program},
  author = {Giddings, L. and Boston, S.},
  year = {1976},
  url = {https://ntrs.nasa.gov/citations/19760020561},
  note = {Source identifier: 19760020561}
}