APA (7th ed.) Citation

United States. Department of Agriculture. Office of the Secretary & Blake, S. F. (1932). Directions for collecting flowering plants and ferns. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Department of Agriculture. Office of the Secretary and S. F. Blake. Directions for Collecting Flowering Plants and Ferns. Washington: U.S. GPO, 1932.

MLA (9th ed.) Citation

United States. Department of Agriculture. Office of the Secretary and S. F. Blake. Directions for Collecting Flowering Plants and Ferns. U.S. GPO, 1932.