@article{363545,
      author = {Card, David E. and Freeman, Richard B.},
      url = {http://library.usi.edu/record/363545},
      title = {Small differences that matter: labor markets and income  maintenance in Canada and the United States /},
      publisher = {University of Chicago Press,},
      recid = {363545},
      pages = {ix, 277 p. :},
      address = {Chicago :},
      year = {1993},
}