The NBER working paper is from 2006, but it was published as a journal article in 2007:

  @article{Fisman2007,
    author = {Raymond Fisman and Edward Miguel},
    title = {Corruption, Norms and Legal Enforcement:
        Evidence from Diplomatic Parking Tickets},
    journal = {Journal of Political Economy},
    volume = 115,
    number = 6,
    year = 2007,
    pages = {1020--48},
  }