?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=+Skhiri+Ha%C3%AFkel&rft.aufirst=Ha%C3%AFkel&rft.aulast=Skhiri&rft.title=Acta+scientiarum+mathematicarum&rft.volume=63&rft.issn=0001-6969&rft.issue=3-4&rft.pages=607-622&rft.atitle=Structure+of+semi-Fredholm+operators+with+fixed+nullity&rft.date=1997&rft.genre=article