@misc{indiciaee263c6e9d8e3,
  title = {Improved density gradient separation techniques using sodium polytungstate and a comparison to the use of other heavy liquids},
  author = {G.L. Skipp and I. K. Brownfield},
  year = {1993},
  doi = {10.3133/ofr92386},
  url = {https://pubs.usgs.gov/publication/ofr92386},
  note = {Source identifier: ofr92386}
}