@misc{indiciae570e90c21f52,
  title = {Climatic change on Mars.},
  author = {Sagan, C. and Toon, O. B. and Gierasch, P. J.},
  year = {1973},
  url = {https://ntrs.nasa.gov/citations/19730056499},
  note = {Source identifier: 19730056499}
}