@misc{indiciaec6cffeff583a,
  title = {Estimating planetary terrain slopes from range measurements using a two dimensional spline smoothing technique},
  author = {Kim, C. S. and Shen, C. N.},
  year = {1982},
  url = {https://ntrs.nasa.gov/citations/19830045377},
  note = {Source identifier: 19830045377}
}