United States. Bureau of the Budget and United States. Office of Management and Budget. "Relation of Budget Authority to Outlays," in United States. Bureau of the Budget and United States. Office of Management and Budget. "Fiscal Year 1971," Budget of the United States Government (February 2, 1970) : 538-539. https://fraser.stlouisfed.org/title/54/item/19025/toc/62071 , accessed on April 18, 2024.