?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=+Nagy+Attila&rft.aufirst=Attila&rft.aulast=Nagy&rft.issue=3&rft.atitle=Retractable+state-finite+automata+without+outputs&rft.title=Acta+cybernetica&rft.volume=16&rft.pages=399-409&rft.issn=0324-721X&rft.date=2004&rft.genre=article