?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Bischoff%2C+M.&rft.aulast=Bischoff&rft.aufirst=M.&rft.date=10+January+2009&rft.title=Coal-mining+induced+events+in+the+Ruhr+area%2C+Germany&rft.genre=proceeding