@misc{indiciae79ca019eaf72,
  title = {Altitude of the top of the Minnekahta Limestone in the Black Hills area, South Dakota},
  author = {Janet M. Carter and Jack A. Redden},
  year = {1999},
  doi = {10.3133/ha744b},
  url = {https://pubs.usgs.gov/publication/ha744B},
  note = {Source identifier: ha744B}
}