@misc{indiciae962034c9c4ff,
  title = {Biostratigraphy and regional relations of the Mississippian Leadville limestone in the San Juan Mountains, southwestern Colorado},
  author = {Augustus K. Armstrong and Bernard L. Mamet},
  year = {1976},
  doi = {10.3133/pp985},
  url = {https://pubs.usgs.gov/publication/pp985},
  note = {Source identifier: pp985}
}