@misc{indiciae697ed752c563,
  title = {Introduction. Oil and gas in the northern part of the Cadiz quadrangle. Ohio. Gas from mud lumps at the mouths of the Mississippi},
  author = {Marius R. Campbell and D. D. Condit and E. W. Shaw},
  year = {1914},
  doi = {10.3133/b541a},
  url = {https://pubs.usgs.gov/publication/b541A},
  note = {Source identifier: b541A}
}