@misc{indiciae57dc4be81677,
  title = {Double-disk solid-phase extraction--Simultaneous cleanup and trace enrichment of herbicides and metabolites from environmental samples},
  author = {Imma Ferrar and Damia Barcelo and E.M. Thurman},
  year = {1999},
  doi = {10.1021/ac980975q},
  url = {https://pubs.usgs.gov/publication/70185250},
  note = {Source identifier: 70185250}
}