@misc{indiciaefb2a8675ab81,
  title = {Karst topography; computer animation and paper model},
  author = {T. R. Alpha and J. P. Galloway and J. C. Tinsley},
  year = {1997},
  doi = {10.3133/ofr97536b},
  url = {https://pubs.usgs.gov/publication/ofr97536B},
  note = {Source identifier: ofr97536B}
}