@article{847439,
      recid = {847439},
      author = {Lerner, Joshua. and Stern, Scott,},
      title = {The rate and direction of inventive activity revisited/},
      publisher = {University of Chicago Press,},
      address = {Chicago :},
      pages = {x, 703 p.},
      year = {2012},
      url = {http://library.usi.edu/record/847439},
}