?url_ver=Z39.88-2004&rft_id=10.1073%2Fpnas.0810478105&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=Fabio&rft.aulast=Pammolli&rft.au=Pammolli%2C+Fabio&rft.issn=1091-6490&rft.atitle=The+size+variance+relationship+of+business+firm+growth+rates&rft.title=Proceedings+of+the+National+Academy+of+Sciences&rft.date=2008&rft.volume=105&rft.issue=50&rft.pages=19595-19600&rft.genre=article