APA (7th ed.) Citation

Combs, W. B. (1953). Grain grading primer. US Gov. Print. Off.

Chicago Style (17th ed.) Citation

Combs, Willis B. Grain Grading Primer. Washington: US Gov. Print. Off, 1953.

MLA (9th ed.) Citation

Combs, Willis B. Grain Grading Primer. US Gov. Print. Off, 1953.