@misc{indiciae0beb2e5e036f,
  title = {New constraints on Precambrian ocean composition},
  author = {Grotzinger, J. P. and Kasting, J. F.},
  year = {1993},
  url = {https://ntrs.nasa.gov/citations/20040090319},
  note = {Source identifier: 20040090319}
}