@misc{indiciae41cb9d4a1334,
  title = {Impact on Comets and Asteroids},
  author = {OKeefe, John D. and Stewart, Sarah T. and Ahrens, Thomas J.},
  year = {2001},
  url = {https://ntrs.nasa.gov/citations/20010044861},
  note = {Source identifier: 20010044861}
}