United States. Postmaster General. (1928). Disposition of surplus stocks of air mail stamp books. U.S. GPO.
Chicago Style (17th ed.) CitationUnited States. Postmaster General. Disposition of Surplus Stocks of Air Mail Stamp Books. Washington: U.S. GPO, 1928.
MLA (9th ed.) CitationUnited States. Postmaster General. Disposition of Surplus Stocks of Air Mail Stamp Books. U.S. GPO, 1928.
Warning: These citations may not always be 100% accurate.