@misc{indiciae9fb01a60392e,
  title = {FORMATIONTOPS (version 1); a system to retrieve formation tops data},
  author = {C. J. Wandrey and R. C. Obuch},
  year = {1990},
  doi = {10.3133/ofr90530},
  url = {https://pubs.usgs.gov/publication/ofr90530},
  note = {Source identifier: ofr90530}
}