?url_ver=Z39.88-2004&rft_id=10.1103%2FPhysRevE.59.R12&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Chessa%2C+Alessandro&rft.aulast=Chessa&rft.aufirst=Alessandro&rft.title=Physical+Review+E&rft.issn=1539-3755&rft.date=January+1999&rft.atitle=Universality+in+sandpiles&rft.volume=59&rft.pages=R12-R15&rft.genre=article