?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=+Libor+Oszk%C3%A1r&rft.aulast=Libor&rft.aufirst=Oszk%C3%A1r&rft.volume=20&rft.issn=0365-8066&rft.title=Acta+mineralogica-petrographica&rft.pages=97-111&rft.atitle=Investigation+of+montmorillonites+treated+by+Urea&rft.date=1971&rft.issue=1&rft.genre=article