@misc{indiciaed0dde7be7a11,
  title = {Process for purification of silicon},
  author = {Rath, H. J. and Sirtl, E. and Pfeiffer, W.},
  year = {1981},
  url = {https://ntrs.nasa.gov/citations/19810018683},
  note = {Source identifier: 19810018683}
}