@misc{indiciae9da9f585005e,
  title = {Size and shape measurements of ash particles from the May 18, 1980, eruption of Mount St. Helens},
  author = {Robert A. Zielinski and Michael B. Sawyer},
  year = {1980},
  doi = {10.3133/ofr81114},
  url = {https://pubs.usgs.gov/publication/ofr81114},
  note = {Source identifier: ofr81114}
}