@misc{indiciae9d694b3a08c8,
  title = {Phase plane displays detect incipient failure in servo system testing},
  author = {Affenito, F. J. and Wohl, J. G.},
  year = {1967},
  url = {https://ntrs.nasa.gov/citations/19670000661},
  note = {Source identifier: 19670000661}
}