?url_ver=Z39.88-2004&rft_id=10.1080%2F00139157.1986.9929898&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Clark%2C+W.&rft.aulast=Clark&rft.aufirst=W.&rft.issue=4&rft.volume=28&rft.date=8+July+1986&rft.issn=0013-9157&rft.atitle=Environmental+History&rft.title=Environment%3A+Science+and+Policy+for+Sustainable+Development&rft.pages=1-1&rft.genre=article