@misc{indiciae1b2df311eb64,
  title = {Preliminary maps of sand/shale ratio in the Cambrian Bonneterre Formation, Rolla 1 degree by 2 degrees Quadrangle, Missouri},
  author = {J. L. Thacker and K. H. Anderson},
  year = {1979},
  doi = {10.3133/mf1002b},
  url = {https://pubs.usgs.gov/publication/mf1002B},
  note = {Source identifier: mf1002B}
}