United States. Postmaster General. (1927). Irregularities in returning undeliverable 2nd, 3rd, and 4th class matter bearing pledge to pay return postage. U.S. GPO.
Chicago Style (17th ed.) CitationUnited States. Postmaster General. Irregularities in Returning Undeliverable 2nd, 3rd, and 4th Class Matter Bearing Pledge to Pay Return Postage. Washington: U.S. GPO, 1927.
MLA (9th ed.) CitationUnited States. Postmaster General. Irregularities in Returning Undeliverable 2nd, 3rd, and 4th Class Matter Bearing Pledge to Pay Return Postage. U.S. GPO, 1927.
Warning: These citations may not always be 100% accurate.