Coba jelasin Daftar karya yang terkenal dari Robert Sterling Yard dong

Sekilas Taman Nasional Kami (1916)

The Top of the Continent (1917)

Our Federal Lands: A Romance of American Development (1928)

Cevasco, G. A. and Richard P Harmond. 2009. Modern American Environmentalists: A Biographical Encyclopedia. Baltimore, MD : Johns Hopkins University Press. .

Dowie, Mark. 1995. Losing Ground : American Environmentalism At the Close of the Twentieth Century . Cambridge, MA: MIT Press. .

Fox, Stephen. 1986. The American Conservation Movement: John Muir and His Legacy. Madison: University of Wisconsin Press. .

Fox, Stephen. 1984. "We Want No Straddlers". Wilderness 48.167 (July): 5–19.

Miles, John C. 1995. Guardians of the Parks: A History of the National Parks and Conservation Association. Washington, DC: Taylor & Francis. .

Sellars, Richard West. 1997. Preserving Nature in the National Parks : A History . New Haven: Yale University Press. .

Sutter, Paul. 2002. Driven Wild: How the Fight against Automobiles Launched the Modern Wilderness Movement. Seattle: University of Washington Press. .