@misc{indiciae2e53dde448c7,
  title = {Recreation management in natural areas: Problems and practices, status and trends},
  author = {R.E. Manning and N.L. Ballinger and J. L. Marion},
  year = {1996},
  url = {https://pubs.usgs.gov/publication/5223259},
  note = {Source identifier: 5223259}
}