@misc{indiciaecd47af5f21fb,
  title = {Sampled-Data Techniques Applied to a Digital Controller for an Altitude Autopilot},
  author = {Schmidt, Stanley F. and Harper, Eleanor V.},
  year = {1959},
  url = {https://ntrs.nasa.gov/citations/19980228405},
  note = {Source identifier: 19980228405}
}