@misc{indiciae360424424ca8,
  title = {Estimated petroleum resources in the former Soviet Union},
  author = {G. F. Ulmishek and C.D. Masters},
  year = {1993},
  doi = {10.3133/ofr93316},
  url = {https://pubs.usgs.gov/publication/ofr93316},
  note = {Source identifier: ofr93316}
}