APA (7th ed.) Zitazioa
Tweed, W. C. (2010). Uncertain path: A search for the future of national parks. University of California Press.
Chicago Style (17th ed.) Zitazioa
Tweed, William C. Uncertain Path: A Search for the Future of National Parks. Berkeley: University of California Press, 2010.
MLA (9th ed.) Zitazioa
Tweed, William C. Uncertain Path: A Search for the Future of National Parks. University of California Press, 2010.
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