?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=Viorel&rft.au=+Barbu+Viorel&rft.aulast=Barbu&rft.title=Acta+scientiarum+mathematicarum&rft.issue=3-4&rft.pages=263-270&rft.date=1969&rft.volume=30&rft.atitle=On+local+properties+of+pseudo-differential+operators&rft.issn=0001-6969&rft.genre=article