@misc{indiciae4e6b0220dcb9,
  title = {The Mexican snakes of the genera Sonora and Chionactis with notes on the status of other Colubrid genera},
  author = {W. H. Stickel},
  year = {1943},
  url = {https://pubs.usgs.gov/publication/5220104},
  note = {Source identifier: 5220104}
}