@misc{indiciae140d74d6d17d,
  title = {Map showing bedrock topography and subcrop of a selected bed beneath alluvial deposits of part of the Henderson Quadrangle, Henderson County, Kentucky},
  author = {T.E. Ball},
  year = {1973},
  doi = {10.3133/i812},
  url = {https://pubs.usgs.gov/publication/i812},
  note = {Source identifier: i812}
}