Yellowstone National Park Protection Act. United States Code, vol. 17, 1872 & supp. 1873, sec. 24. American Memory, memory.loc.gov/cgi-bin/query/r?ammem/consrvbib:@field(NUMBER+@band(amrvl+vl002)). Accessed 12 Jan. 2018.
Moran, Thomas. Painting of Yellowstone. 1871. Birth of a National Park, National Park Services, www.nps.gov/yell/learn/historyculture/yellowstoneestablishment.htm. Accessed 12 Jan. 2018.
Moran, Thomas. Painting of Yellowstone. 1871. Birth of a National Park, National Park Services, www.nps.gov/yell/learn/historyculture/yellowstoneestablishment.htm. Accessed 12 Jan. 2018.