Tunnel No. 2. Red Canyon. East Tunnel.

Chicago citation style
Department of the Interior. National Park Service. (8/25/1916 - 8/10/1933). Tunnel No. 2. Red Canyon. East Tunnel.. 1929-09-25. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/520218. (Accessed June 21, 2018.)
APA citation style
Department of the Interior. National Park Service. (8/25/1916 - 8/10/1933), (1929-09-25) Tunnel No. 2. Red Canyon. East Tunnel.. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/520218
MLA citation style
Department of the Interior. National Park Service. (8/25/1916 - 8/10/1933). Retrieved from the Digital Public Library of America <http://catalog.archives.gov/id/520218>.
Note: These citations are programmatically generated and may be incomplete.