@misc{indiciae374a10449e81,
  title = {The internal structure of sand bars on the Colorado River, Grand Canyon, as determined by ground-penetrating radar},
  author = {Walter A. Barnhardt and Robert Kayen and David Rubin and Diane L. Minasian},
  year = {2001},
  doi = {10.3133/ofr01425},
  url = {https://pubs.usgs.gov/publication/ofr01425},
  note = {Source identifier: ofr01425}
}