@article{IR,
      author = {Graefe, Goetz},
      url = {http://digitalcollections.ohsu.edu/record/3858},
      title = {Relational division: four algorithms and their  performance},
      abstract = {cse-88-022},
      number = {IR},
      doi = {https://doi.org/10.6083/7d278t288},
      recid = {3858},
      address = {1988},
}