@misc{indiciae179e032f8d0a,
  title = {Exploring the Unknown},
  author = {Logsdon, John M. and Garber, Stephen J. and Launius, Roger D.},
  year = {2004},
  url = {https://ntrs.nasa.gov/citations/20040095359},
  note = {Source identifier: 20040095359}
}