?url_ver=Z39.88-2004&rft_id=10.1023%2FA%3A1009701123606&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Hermenegildo&rft.au=Hermenegildo%2C+Manuel+V.&rft.aufirst=Manuel+V.&rft.atitle=Some+challenges+for+constraint+programming&rft.issue=1&rft.volume=2&rft.date=April+1997&rft.issn=1383-7133&rft.title=The+Constraints+Journal&rft.pages=63-69&rft.genre=article