@misc{indiciaed2b3a744432f,
  title = {Geologic map of the Alexandria quadrangle, Campbell and Kenton Counties, Kentucky},
  author = {A. B. Gibbons},
  year = {1971},
  doi = {10.3133/gq926},
  url = {https://pubs.usgs.gov/publication/gq926},
  note = {Source identifier: gq926}
}