@misc{indiciaec3d40fb45219,
  title = {Results of external quality-assurance program for the National Atmospheric Deposition Program and National Trends Network during 1985},
  author = {M. H. Brooks and L.J. Schroder and T. C. Willoughby},
  year = {1988},
  doi = {10.3133/wri874219},
  url = {https://pubs.usgs.gov/publication/wri874219},
  note = {Source identifier: wri874219}
}