@misc{indiciae7faad7339c3d,
  title = {Interstellar communication},
  author = {Machol, R. E. and Van Vleck, E. and Evans, L. C.},
  year = {1975},
  url = {https://ntrs.nasa.gov/citations/19760027150},
  note = {Source identifier: 19760027150}
}