?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Gatti%2C+Roberto+Cazzolla&rft.aufirst=Roberto+Cazzolla&rft.aulast=Gatti&rft.volume=119&rft.title=Proceedings+of+The+National+Academy+of+Sciences+of+the+United+States+of+America+(PNAS)&rft.date=31+January+2022&rft.atitle=The+number+of+tree+species+on+Earth&rft.issue=6&rft.genre=article