?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=+Sipos+S%C3%A1ndor&rft.aulast=Sipos&rft.aufirst=S%C3%A1ndor&rft.volume=27&rft.issn=0001-6721&rft.title=Acta+physica+et+chemica&rft.pages=135-140&rft.atitle=Infrared+spectroscopic+examination+oh+humic+acids+3.&rft.date=1981&rft.issue=1-4&rft.genre=article