Federal Reserve Bank of Dallas. "Expansion Book-Entry Procedure for Treasury Securities, Circular No. 69-202," District Notices (Federal Reserve Bank of Dallas) (September 1, 1969). https://fraser.stlouisfed.org/scribd/?item_id=544218&filepath=/files/docs/historical/frbdal/circulars/frbdallas_circ_19690901_no69-202.pdf&start_page=1, accessed on September 24, 2017.
Expansion Book-entry Procedure for Treasury Securities; Subpart O Treasury Department Circular No. 300; Fiscal Agency Operating Circular No. 3; Bulletin No. 7