United States. Post Office Department. (1929). List of postal supplies furnished post offices of 1st and 2nd classes, post office inspectors, and Railway Mail Service. GPO.
Chicago Style (17th ed.) CitationUnited States. Post Office Department. List of Postal Supplies Furnished Post Offices of 1st and 2nd Classes, Post Office Inspectors, and Railway Mail Service. [Washington]: GPO, 1929.
MLA (9th ed.) CitationUnited States. Post Office Department. List of Postal Supplies Furnished Post Offices of 1st and 2nd Classes, Post Office Inspectors, and Railway Mail Service. GPO, 1929.
Warning: These citations may not always be 100% accurate.