@misc{indiciaec93eadd87038,
  title = {Petroleum geology and resources of the middle Caspian Basin, Former Soviet Union},
  author = {Gregory F. Ulmishek},
  year = {2001},
  doi = {10.3133/b2201a},
  url = {https://pubs.usgs.gov/publication/b2201A},
  note = {Source identifier: b2201A}
}