@misc{207161,
  author = {Ellen Voorhees and Donna Harman},
  title = {The Ninth Text REtrieval Conference (TREC-9)},
  year = {2001},
  month = {2001-10-01},
  publisher = {Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NIST.SP.500-249},
  language = {en},
}