@article{202,
  author = {Piet Hut and Walter Alvarez and William Elder and Thor Hansen and Erle Kauffman and Gerta Keller and Eugene Shoemaker and Paul Weissman},
  title = {Comet showers as a cause of mass extinctions},
  abstract = {<p>If at least some mass extinctions are caused by impacts, why do they extend over intervals of one to three million years and have a partly stepwise character? The solution may be provided by multiple cometary impacts. Astronomical, geological and palaeontological evidence is consistent with a causal connection between comet showers, clusters of impact events and stepwise mass extinctions, but it is too early to tell how pervasive this relationship may be.\&nbsp; <a href="https://geoweb.princeton.edu/research/keller/pubs/Hut-1987-Nature.pdf" target="_blank">PDF</a></p>
},
  year = {1987},
  journal = {Nature},
  volume = {329},
  pages = {118{\textendash}126},
  month = {sep},
  url = {https://doi.org/10.1038/329118a0},
  doi = {10.1038/329118a0},
  language = {eng},
}