APA (7th ed.) Citation

United States. Bureau of Customs. (1938). Sampling guide. [s.n.].

Chicago Style (17th ed.) Citation

United States. Bureau of Customs. Sampling Guide. [Washington]: [s.n.], 1938.

MLA (9th ed.) Citation

United States. Bureau of Customs. Sampling Guide. [s.n.], 1938.

Warning: These citations may not always be 100% accurate.