@misc{indiciaef9ad96af44fa,
  title = {The debate over the Cretaceous-Tertiary boundary},
  author = {Alvarez, W. and Asaro, F. and Alvarez, L. W. and Michel, H. V.},
  year = {1988},
  url = {https://ntrs.nasa.gov/citations/19890011917},
  note = {Source identifier: 19890011917}
}