APA

United States, . (2019). Challenges in gateway communities of national parks: field hearing before the Subcommittee on National Parks of the Committee on Energy and Natural Resources, United States Senate, One Hundred Fifteenth Congress, second session, October 19, 2018. Washington: U.S. Government Publishing Office.

Chicago

United States, . 2019. Challenges in gateway communities of national parks: field hearing before the Subcommittee on National Parks of the Committee on Energy and Natural Resources, United States Senate, One Hundred Fifteenth Congress, second session, October 19, 2018. Washington: U.S. Government Publishing Office.

Harvard

United States, . (2019). Challenges in gateway communities of national parks: field hearing before the Subcommittee on National Parks of the Committee on Energy and Natural Resources, United States Senate, One Hundred Fifteenth Congress, second session, October 19, 2018. Washington: U.S. Government Publishing Office.

MLA

United States, . Challenges in gateway communities of national parks: field hearing before the Subcommittee on National Parks of the Committee on Energy and Natural Resources, United States Senate, One Hundred Fifteenth Congress, second session, October 19, 2018. Washington: U.S. Government Publishing Office. 2019.