@misc{indiciaee2e23796571c,
  title = {Unified Engineering Software System},
  author = {Purves, L. R. and Gordon, S. and Peltzman, A. and Dube, M.},
  year = {1989},
  url = {https://ntrs.nasa.gov/citations/19890000072},
  note = {Source identifier: 19890000072}
}