@misc{indiciae9a285bcc4d29,
  title = {MECHANICAL ELEMENTS FOR VACUUM OPERATION},
  author = {Evans, H. E. and Federline, M. F. and Flatley, T. W.},
  year = {1962},
  url = {https://ntrs.nasa.gov/citations/19630001404},
  note = {Source identifier: 19630001404}
}