APA (7th ed.) Citation

United States. National Park Service. Office of Communications, United States. National Park Service. Office of Legislative and Congressional Affairs, Harpers Ferry Center (U.S.), United States. National Park Service. Office of Public Affairs, & United States. National Park Service. Division of Publications. The national parks, index. The Office of Public Affairs, and the Division of Publications, National Park Service.

Chicago Style (17th ed.) Citation

United States. National Park Service. Office of Communications, United States. National Park Service. Office of Legislative and Congressional Affairs, Harpers Ferry Center (U.S.), United States. National Park Service. Office of Public Affairs, and United States. National Park Service. Division of Publications. The National Parks, Index. Washington, D.C.: The Office of Public Affairs, and the Division of Publications, National Park Service.

MLA (9th ed.) Citation

United States. National Park Service. Office of Communications, et al. The National Parks, Index. The Office of Public Affairs, and the Division of Publications, National Park Service.