APA (7th ed.) Citation

(1920). U.S. trade in chewing gum and chicle. GPO.

Chicago Style (17th ed.) Citation

U.S. Trade in Chewing Gum and Chicle. [Washington]: GPO, 1920.

MLA (9th ed.) Citation

U.S. Trade in Chewing Gum and Chicle. GPO, 1920.

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