APA (7th ed.) Citation

Piper, C. V. (1922). Important cultivated grasses. U.S. Dept. of Agriculture.

Chicago Style (17th ed.) Citation

Piper, Charles V. Important Cultivated Grasses. Washington, D.C.: U.S. Dept. of Agriculture, 1922.

MLA (9th ed.) Citation

Piper, Charles V. Important Cultivated Grasses. U.S. Dept. of Agriculture, 1922.