@misc{indiciae16e0d749c0b8,
  title = {The seven-story river; geomorphology of the Potomac River Channel between Blockhouse Point, Maryland, and Georgetown, District of Columbia, with emphasis on the gorge complex below Great Falls},
  author = {E-an Zen},
  year = {1997},
  doi = {10.3133/ofr9760},
  url = {https://pubs.usgs.gov/publication/ofr9760},
  note = {Source identifier: ofr9760}
}