@misc{indiciaed811d7b20e96,
  title = {The rapids and the pools - Grand Canyon: Chapter D in The Colorado River region and John Wesley Powell (Professional Paper 669)},
  author = {Luna Bergere Leopold},
  year = {1969},
  doi = {10.3133/pp669d},
  url = {https://pubs.usgs.gov/publication/pp669D},
  note = {Source identifier: pp669D}
}