@book{eprints42,
           month = {December},
       publisher = {Cambridge University Press},
            note = {For replication data, see: http://www.comparativeconstitutionsproject.org/Downloads.aspx (registration required)},
         address = {Cambridge; New York},
          author = {Zachary Elkins and Tom Ginsburg and James Melton},
           title = {The Endurance of National Constitutions},
            year = {2009},
             url = {http://eprints.imtlucca.it/42/}
}