?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Errera%2C+Paul&rft.aulast=Errera&rft.aufirst=Paul&rft.date=1920&rft.btitle=Belgique.+Cinquante+ans+de+droit+public+(1869-1919)&rft.tpages=43&rft.genre=book