@misc{indiciaee28a8ce9287a,
  title = {Terminal-Area Guidance Algorithms for Automated Air-Traffic Control},
  author = {Erzberger, H. and Lee, H. Q.},
  year = {1972},
  url = {https://ntrs.nasa.gov/citations/19720015367},
  note = {Source identifier: 19720015367}
}