APA (7th ed.) Citation

U.S. Customs Service. (1990). Trademark information for travelers (Rev. May 1990.). The Service.

Chicago Style (17th ed.) Citation

U.S. Customs Service. Trademark Information for Travelers. Rev. May 1990. Washington, D.C.: The Service, 1990.

MLA (9th ed.) Citation

U.S. Customs Service. Trademark Information for Travelers. Rev. May 1990. The Service, 1990.

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