@misc{indiciaedf52f28ba8b5,
  title = {The visual accumulation tube for sedimentation analysis of sands},
  author = {B.C. Colby and R.P. Christensen},
  year = {1955},
  doi = {10.3133/ofr5529},
  url = {https://pubs.usgs.gov/publication/ofr5529},
  note = {Source identifier: ofr5529}
}