?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Valero+Ubierna%2C+Constantino&rft.aulast=Valero+Ubierna&rft.aufirst=Constantino&rft.issue=249&rft.pages=58-61&rft.atitle=Las+nuevas+cosechadoras%3A+mas+rotativas%2C+m%C3%A1s+grandes%2C+m%C3%A1s+capaces+que+nunca&rft.title=Vida+Rural&rft.date=May+2007&rft.issn=1133-8938&rft.genre=article