@misc{indiciaebd64ecf518af,
  title = {A simple model of a man-machine development cycle, part A},
  author = {Leonard, J. N. and Wulff, J. J.},
  year = {1968},
  url = {https://ntrs.nasa.gov/citations/19680004794},
  note = {Source identifier: 19680004794}
}