APA (7th ed.) Citation

Little, E. L., & Viereck, L. A. (1977). Atlas of United States trees. U.S. Dep. of Agriculture, Forest Service.

Chicago Style (17th ed.) Citation

Little, Elbert Luther, and Leslie A. Viereck. Atlas of United States Trees. Washington, DC: U.S. Dep. of Agriculture, Forest Service, 1977.

MLA (9th ed.) Citation

Little, Elbert Luther, and Leslie A. Viereck. Atlas of United States Trees. U.S. Dep. of Agriculture, Forest Service, 1977.