Cita APA

Duncan, D. (2009). The national parks: America's best idea : an illustrated history. New York: Alfred A. Knopf.

Chicago Style Citation

Duncan, Dayton. The National Parks: America's Best Idea : An Illustrated History. New York: Alfred A. Knopf, 2009.

Cita MLA

Duncan, Dayton. The National Parks: America's Best Idea : An Illustrated History. New York: Alfred A. Knopf, 2009.