@misc{indiciae8a0e9825c2e7,
  title = {Biostratigraphic classification of the marine Triassic in North America},
  author = {N. J. Silberling and E. T. Tozer},
  year = {1968},
  doi = {10.1130/spe110-p1},
  url = {https://pubs.usgs.gov/publication/70209121},
  note = {Source identifier: 70209121}
}