@misc{indiciae7165910d17c6,
  title = {Formation of regolith-collapse sinkholes in southern Illinois: Interpretation and identification of associated buried cavities},
  author = {S.V. Panno and C.P. Wiebel and P.C. Heigold and P.C. Reed},
  year = {1994},
  doi = {10.1007/bf00771791},
  url = {https://pubs.usgs.gov/publication/70017045},
  note = {Source identifier: 70017045}
}