@misc{indiciae8aaa1e7e2e05,
  title = {PUZZLE - A program for computer-aided design of printed circuit artwork},
  author = {Harrell, D. A. W. and Zane, R.},
  year = {1971},
  url = {https://ntrs.nasa.gov/citations/19710000121},
  note = {Source identifier: 19710000121}
}