@misc{indiciae84c48dd1c931,
  title = {Relative sea-level changes during Middle Ordovician through Mississippian deposition in the Iowa area, North American craton},
  author = {B.J. Witzke and B.J. Bunker},
  year = {1996},
  url = {https://pubs.usgs.gov/publication/70017837},
  note = {Source identifier: 70017837}
}