United States. Congress. House. Committee on Interior and Insular Affairs. Subcommittee on National Parks and Recreation. (1968). The North Cascades: Hearings, Ninetieth Congress, second session .. U.S. Govt. Print. Off..
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)United States. Congress. House. Committee on Interior and Insular Affairs. Subcommittee on National Parks and Recreation. The North Cascades: Hearings, Ninetieth Congress, Second Session .. Washington: U.S. Govt. Print. Off., 1968.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)United States. Congress. House. Committee on Interior and Insular Affairs. Subcommittee on National Parks and Recreation. The North Cascades: Hearings, Ninetieth Congress, Second Session .. U.S. Govt. Print. Off., 1968.
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