@misc{indiciaea8abc210eb3d,
  title = {Assessment of air quality and air pollutant impacts in national parks of the Rocky Mountains and northern Great Plains},
  author = {David L. Peterson and T.J. Sullivan and J.M. Eilers and S. Brace and D. Horner},
  year = {1998},
  url = {https://pubs.usgs.gov/publication/70194374},
  note = {Source identifier: 70194374}
}