?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Ponsard%2C+Christophe&rft.aulast=Ponsard&rft.aufirst=Christophe&rft.date=26+May+2011&rft.title=Generating+High-Level+Event-B+System+Models+from+KAOS+Requirements+Models&rft.genre=proceeding