American Antiquities Act of 1906; Passed into Law on June 8, 1906Sec. 2. That the President of the United States is hereby authorized, in his discretion, to declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are situated upon the lands owned or controlled by the Government of the United States to be national monuments, and may reserve as a part thereof parcels of land, the limits of which in all cases shall be confined to the smallest area compatible with proper care and management of the objects to be protected
"U.S. Congress: American Antiquities Act of 1906; Passed into Law on June 8, 1906." Gilded Age and Progressive Era Reference Library, edited by Lawrence W. Baker and Rebecca Valentine, vol. 3: Primary Source, UXL, 2007, pp. 139-149. U.S. History in Context, http://link.galegroup.com/apps/doc/CX2587800077/UHIC?u=j071909004&sid=UHIC&xid=e4cd132d. Accessed 16 Dec. 2018.