APA (7th ed.) Citation

United States Postal Service. (1984). Certified mail. U.S. Postal Service.

Chicago Style (17th ed.) Citation

United States Postal Service. Certified Mail. Washington, DC: U.S. Postal Service, 1984.

MLA (9th ed.) Citation

United States Postal Service. Certified Mail. U.S. Postal Service, 1984.

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