Duncan, D. (2009). The national parks: America's best idea : an illustrated history. New York: Alfred A. Knopf.
Stile di citazione ChicagoDuncan, Dayton. The National Parks: America's Best Idea : An Illustrated History. New York: Alfred A. Knopf, 2009.
Citazione MLADuncan, Dayton. The National Parks: America's Best Idea : An Illustrated History. New York: Alfred A. Knopf, 2009.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.