?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=A+K&rft.au=Singh%2C+A+K&rft.aulast=Singh&rft.atitle=Ploidy+manipulations+for+interspecific+gene+transfer&rft.title=Advances+in+Agronomy+&rft.issn=0065-2113&rft.date=1990&rft.volume=43&rft.pages=199-240&rft.genre=article