@misc{indiciae6f8a0acec95c,
  title = {Candidate cave entrances on Mars},
  author = {Glen E. Cushing},
  year = {2012},
  doi = {10.4311/2010ex0167r},
  url = {https://pubs.usgs.gov/publication/70039388},
  note = {Source identifier: 70039388}
}