?url_ver=Z39.88-2004&rft_id=10.1103%2FPhysRevLett.86.1896&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Felici%2C+Maddalena&rft.aulast=Felici&rft.aufirst=Maddalena&rft.atitle=Perturbative+approach+to+the+Bak-Sneppen+model&rft.title=Physical+Review+Letters&rft.issue=9&rft.volume=86&rft.date=February+2001&rft.pages=1896-1899&rft.issn=0031-9007&rft.genre=article