Federal Reserve Bank of Dallas. "U.S. Postal Service Money Orders, Circular No. 81-67," District Notices (Federal Reserve Bank of Dallas) (April 6, 1981). https://fraser.stlouisfed.org/scribd/?item_id=541250&filepath=/files/docs/historical/frbdal/circulars/frbdallas_circ_19810406_no81-067.pdf&start_page=1, accessed on September 22, 2017.
Changes Made to Both Domestic and Military Money Orders. Maximum Value Increased to $500. United States Postal Service Seal and Limitation Values No Longer Imprinted.