@misc{indiciaeab75e148c21c,
  title = {Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1971},
  author = {George Vincent Cohee and W.B. Wright},
  year = {1972},
  doi = {10.3133/b1372a},
  url = {https://pubs.usgs.gov/publication/b1372A},
  note = {Source identifier: b1372A}
}