APA (7th ed.) Citation

United States. National Park Service. Great Smoky Mountains National Park trail map, North Carolina/Tennesee (Scale [ca. 1:168,000].). The Service.

Chicago Style (17th ed.) Citation

United States. National Park Service. Great Smoky Mountains National Park Trail Map, North Carolina/Tennesee. Scale [ca. 1:168,000]. [Washington, D.C.?]: The Service.

MLA (9th ed.) Citation

United States. National Park Service. Great Smoky Mountains National Park Trail Map, North Carolina/Tennesee. Scale [ca. 1:168,000]. The Service.