National Park Service entrance fees : hearing before the Subcommittee on Public Lands, National Parks and Forests of the Committee on Energy and Natural Resources, United States Senate, one hundredth congress, first session of H.R. 1320.
United States.Congress.Senate.Committee on Energy and Natural Resources.Subcommittee on Public Lands, National Parks and Forests.
Washington : Government Printing Office,
1987.
National parks and reserves